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The Xbox 360's original graphical user interface was the Xbox 360 Dashboard; a tabbed interface that featured five "Blades" (formerly four blades), and was designed by AKQA and Audiobrain. It could be launched automatically when the console booted without a disc in it, or when the disc tray was ejected, but the user had the option to select what the console does if a game is in the tray on start up, or if inserted when already on. A simplified version of it was also accessible at any time via the Xbox Guide button on the gamepad. This simplified version showed the user's gamercard, Xbox Live messages and friends list. It also allowed for personal and music settings, in addition to voice or video chats, or returning to the Xbox Dashboard from the game. |
Xbox Live Arcade is an online service operated by Microsoft that is used to distribute downloadable video games to Xbox and Xbox 360 owners. In addition to classic arcade games such as Ms. Pac-Man, the service offers some new original games like Assault Heroes. The Xbox Live Arcade also features games from other consoles, such as the PlayStation game Castlevania: Symphony of the Night and PC games such as Zuma. The service was first launched on November 3, 2004, using a DVD to load, and offered games for about US$5 to $15. Items are purchased using Microsoft Points, a proprietary currency used to reduce credit card transaction charges. On November 22, 2005, Xbox Live Arcade was re-launched with the release of the Xbox 360, in which it was now integrated with the Xbox 360's dashboard. The games are generally aimed toward more casual gamers; examples of the more popular titles are Geometry Wars, Street Fighter II' Hyper Fighting, and Uno. On March 24, 2010, Microsoft introduced the Game Room to Xbox Live. Game Room is a gaming service for Xbox 360 and Microsoft Windows that lets players compete in classic arcade and console games in a virtual arcade. |
At the 2007, 2008, and 2009 Consumer Electronics Shows, Microsoft had announced that IPTV services would soon be made available to use through the Xbox 360. In 2007, Microsoft chairman Bill Gates stated that IPTV on Xbox 360 was expected to be available to consumers by the holiday season, using the Microsoft TV IPTV Edition platform. In 2008, Gates and president of Entertainment & Devices Robbie Bach announced a partnership with BT in the United Kingdom, in which the BT Vision advanced TV service, using the newer Microsoft Mediaroom IPTV platform, would be accessible via Xbox 360, planned for the middle of the year. BT Vision's DVR-based features would not be available on Xbox 360 due to limited hard drive capacity. In 2010, while announcing version 2.0 of Microsoft Mediaroom, Microsoft CEO Steve Ballmer mentioned that AT&T's U-verse IPTV service would enable Xbox 360s to be used as set-top boxes later in the year. As of January 2010, IPTV on Xbox 360 has yet to be deployed beyond limited trials. |
The Xbox Live Marketplace is a virtual market designed for the console that allows Xbox Live users to download purchased or promotional content. The service offers movie and game trailers, game demos, Xbox Live Arcade games and Xbox 360 Dashboard themes as well as add-on game content (items, costumes, levels etc.). These features are available to both Free and Gold members on Xbox Live. A hard drive or memory unit is required to store products purchased from Xbox Live Marketplace. In order to download priced content, users are required to purchase Microsoft Points for use as scrip; though some products (such as trailers and demos) are free to download. Microsoft Points can be obtained through prepaid cards in 1,600 and 4,000-point denominations. Microsoft Points can also be purchased through Xbox Live with a credit card in 500, 1,000, 2,000 and 5,000-point denominations. Users are able to view items available to download on the service through a PC via the Xbox Live Marketplace website. An estimated seventy percent of Xbox Live users have downloaded items from the Marketplace. |
Launched worldwide across 2005–2006, the Xbox 360 was initially in short supply in many regions, including North America and Europe. The earliest versions of the console suffered from a high failure rate, indicated by the so-called "Red Ring of Death", necessitating an extension of the device's warranty period. Microsoft released two redesigned models of the console: the Xbox 360 S in 2010, and the Xbox 360 E in 2013. As of June 2014, 84 million Xbox 360 consoles have been sold worldwide, making it the sixth-highest-selling video game console in history, and the highest-selling console made by an American company. Although not the best-selling console of its generation, the Xbox 360 was deemed by TechRadar to be the most influential through its emphasis on digital media distribution and multiplayer gaming on Xbox Live. The Xbox 360's successor, the Xbox One, was released on November 22, 2013. Microsoft has stated they plan to support the Xbox 360 until 2016. The Xbox One is also backwards compatible with the Xbox 360. |
In May 2008 Microsoft announced that 10 million Xbox 360s had been sold and that it was the "first current generation gaming console" to surpass the 10 million figure in the US. In the US, the Xbox 360 was the leader in current-generation home console sales until June 2008, when it was surpassed by the Wii. The Xbox 360 has sold a total of 870,000 units in Canada as of August 1, 2008. Between January 2011 and October 2013, the Xbox 360 was the best-selling console in the United States for these 32 consecutive months. |
TechRadar deemed the Xbox 360 as the most influential game system through its emphasis of digital media distribution, Xbox Live online gaming service, and game achievement feature. During the console's lifetime, the Xbox brand has grown from gaming-only to encompassing all multimedia, turning it into a hub for "living-room computing environment". Five years after the Xbox 360's original debut, the well-received Kinect motion capture camera was released, which became the fastest selling consumer electronic device in history, and extended the life of the console. |
Kinect is a "controller-free gaming and entertainment experience" for the Xbox 360. It was first announced on June 1, 2009 at the Electronic Entertainment Expo, under the codename, Project Natal. The add-on peripheral enables users to control and interact with the Xbox 360 without a game controller by using gestures, spoken commands and presented objects and images. The Kinect accessory is compatible with all Xbox 360 models, connecting to new models via a custom connector, and to older ones via a USB and mains power adapter. During their CES 2010 keynote speech, Robbie Bach and Microsoft CEO Steve Ballmer went on to say that Kinect will be released during the holiday period (November–January) and it will work with every 360 console. Its name and release date of 2010-11-04 were officially announced on 2010-06-13, prior to Microsoft's press conference at E3 2010. |
Since these problems surfaced, Microsoft has attempted to modify the console to improve its reliability. Modifications include a reduction in the number, size, and placement of components, the addition of dabs of epoxy on the corners and edges of the CPU and GPU as glue to prevent movement relative to the board during heat expansion, and a second GPU heatsink to dissipate more heat. With the release of the redesigned Xbox 360 S, the warranty for the newer models does not include the three-year extended coverage for "General Hardware Failures". The newer Xbox 360 S model indicates system overheating when the console's power button begins to flash red, unlike previous models where the first and third quadrant of the ring would light up red around the power button if overheating occurred. The system will then warn the user of imminent system shutdown until the system has cooled, whereas a flashing power button that alternates between green and red is an indication of a "General Hardware Failure" unlike older models where three of the quadrants would light up red. |
On November 6, 2006, Microsoft announced the Xbox Video Marketplace, an exclusive video store accessible through the console. Launched in the United States on November 22, 2006, the first anniversary of the Xbox 360's launch, the service allows users in the United States to download high-definition and standard-definition television shows and movies onto an Xbox 360 console for viewing. With the exception of short clips, content is not currently available for streaming, and must be downloaded. Movies are also available for rental. They expire in 14 days after download or at the end of the first 24 hours after the movie has begun playing, whichever comes first. Television episodes can be purchased to own, and are transferable to an unlimited number of consoles. Downloaded files use 5.1 surround audio and are encoded using VC-1 for video at 720p, with a bitrate of 6.8 Mbit/s. Television content is offered from MTV, VH1, Comedy Central, Turner Broadcasting, and CBS; and movie content is Warner Bros., Paramount, and Disney, along with other publishers. |
While the original Xbox sold poorly in Japan, selling just 2 million units while it was on the market (between 2002 and 2005),[citation needed] the Xbox 360 sold even more poorly, selling only 1.5 million units from 2005 to 2011. Edge magazine reported in August 2011 that initially lackluster and subsequently falling sales in Japan, where Microsoft had been unable to make serious inroads into the dominance of domestic rivals Sony and Nintendo, had led to retailers scaling down and in some cases discontinuing sales of the Xbox 360 completely. |
Two major hardware revisions of the Xbox 360 have succeeded the original models; the Xbox 360 S (also referred to as the "Slim") replaced the original "Elite" and "Arcade" models in 2010. The S model carries a smaller, streamlined appearance with an angular case, and utilizes a redesigned motherboard designed to alleviate the hardware and overheating issues experienced by prior models. It also includes a proprietary port for use with the Kinect sensor. The Xbox 360 E, a further streamlined variation of the 360 S with a two-tone rectangular case inspired by Xbox One, was released in 2013. In addition to its revised aesthetics, Xbox 360 E also has one fewer USB port and no longer supports S/PDIF. |
Six games were initially available in Japan, while eagerly anticipated titles such as Dead or Alive 4 and Enchanted Arms were released in the weeks following the console's launch. Games targeted specifically for the region, such as Chromehounds, Ninety-Nine Nights, and Phantasy Star Universe, were also released in the console's first year. Microsoft also had the support of Japanese developer Mistwalker, founded by Final Fantasy creator Hironobu Sakaguchi. Mistwalker's first game, Blue Dragon, was released in 2006 and had a limited-edition bundle which sold out quickly with over 10,000 pre-orders. Blue Dragon is one of three Xbox 360 games to surpass 200,000 units in Japan, along with Tales of Vesperia and Star Ocean: The Last Hope. Mistwalker's second game, Lost Odyssey also sold over 100,000 copies. |
Music, photos and videos can be played from standard USB mass storage devices, Xbox 360 proprietary storage devices (such as memory cards or Xbox 360 hard drives), and servers or computers with Windows Media Center or Windows XP with Service pack 2 or higher within the local-area network in streaming mode. As the Xbox 360 uses a modified version of the UPnP AV protocol, some alternative UPnP servers such as uShare (part of the GeeXboX project) and MythTV can also stream media to the Xbox 360, allowing for similar functionality from non-Windows servers. This is possible with video files up to HD-resolution and with several codecs (MPEG-2, MPEG-4, WMV) and container formats (WMV, MOV, TS). |
Xbox Live Gold includes the same features as Free and includes integrated online game playing capabilities outside of third-party subscriptions. Microsoft has allowed previous Xbox Live subscribers to maintain their profile information, friends list, and games history when they make the transition to Xbox Live Gold. To transfer an Xbox Live account to the new system, users need to link a Windows Live ID to their gamertag on Xbox.com. When users add an Xbox Live enabled profile to their console, they are required to provide the console with their passport account information and the last four digits of their credit card number, which is used for verification purposes and billing. An Xbox Live Gold account has an annual cost of US$59.99, C$59.99, NZ$90.00, GB£39.99, or €59.99. As of January 5, 2011, Xbox Live has over 30 million subscribers. |
On May 26, 2009, Microsoft announced the future release of the Zune HD (in the fall of 2009), the next addition to the Zune product range. This is of an impact on the Xbox Live Video Store as it was also announced that the Zune Video Marketplace and the Xbox Live Video Store will be merged to form the Zune Marketplace, which will be arriving on Xbox Live in 7 countries initially, the United Kingdom, the United States, France, Italy, Germany, Ireland and Spain. Further details were released at the Microsoft press conference at E3 2009. |
Beginning in 1689, the colonies became involved in a series of wars between Great Britain and France for control of North America, the most important of which were Queen Anne's War, in which the British conquered French colony Acadia, and the final French and Indian War (1754–63) when Britain was victorious over all the French colonies in North America. This final war was to give thousands of colonists, including Virginia colonel George Washington, military experience which they put to use during the American Revolutionary War. |
By far the largest military action in which the United States engaged during this era was the War of 1812. With Britain locked in a major war with Napoleon's France, its policy was to block American shipments to France. The United States sought to remain neutral while pursuing overseas trade. Britain cut the trade and impressed seamen on American ships into the Royal Navy, despite intense protests. Britain supported an Indian insurrection in the American Midwest, with the goal of creating an Indian state there that would block American expansion. The United States finally declared war on the United Kingdom in 1812, the first time the U.S. had officially declared war. Not hopeful of defeating the Royal Navy, the U.S. attacked the British Empire by invading British Canada, hoping to use captured territory as a bargaining chip. The invasion of Canada was a debacle, though concurrent wars with Native Americans on the western front (Tecumseh's War and the Creek War) were more successful. After defeating Napoleon in 1814, Britain sent large veteran armies to invade New York, raid Washington and capture the key control of the Mississippi River at New Orleans. The New York invasion was a fiasco after the much larger British army retreated to Canada. The raiders succeeded in the burning of Washington on 25 August 1814, but were repulsed in their Chesapeake Bay Campaign at the Battle of Baltimore and the British commander killed. The major invasion in Louisiana was stopped by a one-sided military battle that killed the top three British generals and thousands of soldiers. The winners were the commanding general of the Battle of New Orleans, Major General Andrew Jackson, who became president and the Americans who basked in a victory over a much more powerful nation. The peace treaty proved successful, and the U.S. and Britain never again went to war. The losers were the Indians, who never gained the independent territory in the Midwest promised by Britain. |
Secretary of War Elihu Root (1899–1904) led the modernization of the Army. His goal of a uniformed chief of staff as general manager and a European-type general staff for planning was stymied by General Nelson A. Miles but did succeed in enlarging West Point and establishing the U.S. Army War College as well as the General Staff. Root changed the procedures for promotions and organized schools for the special branches of the service. He also devised the principle of rotating officers from staff to line. Root was concerned about the Army's role in governing the new territories acquired in 1898 and worked out the procedures for turning Cuba over to the Cubans, and wrote the charter of government for the Philippines. |
The United States originally wished to remain neutral when World War I broke out in August 1914. However, it insisted on its right as a neutral party to immunity from German submarine attack, even though its ships carried food and raw materials to Britain. In 1917 the Germans resumed submarine attacks, knowing that it would lead to American entry. When the U.S declared war, the U.S. army was still small by European standards and mobilization would take a year. Meanwhile, the U.S. continued to provide supplies and money to Britain and France, and initiated the first peacetime draft. Industrial mobilization took longer than expected, so divisions were sent to Europe without equipment, relying instead on the British and French to supply them. |
Memories and lessons from the war are still a major factor in American politics. One side views the war as a necessary part of the Containment policy, which allowed the enemy to choose the time and place of warfare. Others note the U.S. made major strategic gains as the Communists were defeated in Indonesia, and by 1972 both Moscow and Beijing were competing for American support, at the expense of their allies in Hanoi. Critics see the conflict as a "quagmire"—an endless waste of American blood and treasure in a conflict that did not concern US interests. Fears of another quagmire have been major factors in foreign policy debates ever since. The draft became extremely unpopular, and President Nixon ended it in 1973, forcing the military (the Army especially) to rely entirely upon volunteers. That raised the issue of how well the professional military reflected overall American society and values; the soldiers typically took the position that their service represented the highest and best American values. |
The Persian Gulf War was a conflict between Iraq and a coalition force of 34 nations led by the United States. The lead up to the war began with the Iraqi invasion of Kuwait in August 1990 which was met with immediate economic sanctions by the United Nations against Iraq. The coalition commenced hostilities in January 1991, resulting in a decisive victory for the U.S. led coalition forces, which drove Iraqi forces out of Kuwait with minimal coalition deaths. Despite the low death toll, over 180,000 US veterans would later be classified as "permanently disabled" according to the US Department of Veterans Affairs (see Gulf War Syndrome). The main battles were aerial and ground combat within Iraq, Kuwait and bordering areas of Saudi Arabia. Land combat did not expand outside of the immediate Iraq/Kuwait/Saudi border region, although the coalition bombed cities and strategic targets across Iraq, and Iraq fired missiles on Israeli and Saudi cities. |
US troops participated in a UN peacekeeping mission in Somalia beginning in 1992. By 1993 the US troops were augmented with Rangers and special forces with the aim of capturing warlord Mohamed Farrah Aidid, whose forces had massacred peacekeepers from Pakistan. During a raid in downtown Mogadishu, US troops became trapped overnight by a general uprising in the Battle of Mogadishu. Eighteen American soldiers were killed, and a US television crew filmed graphic images of the body of one soldier being dragged through the streets by an angry mob. Somali guerrillas paid a staggering toll at an estimated 1,000–5,000 total casualties during the conflict. After much public disapproval, American forces were quickly withdrawn by President Bill Clinton. The incident profoundly affected US thinking about peacekeeping and intervention. The book Black Hawk Down was written about the battle, and was the basis for the later movie of the same name. |
In January 2002, the U.S. sent more than 1,200 troops (later raised to 2,000) to assist the Armed Forces of the Philippines in combating terrorist groups linked to al-Qaida, such as Abu Sayyaf, under Operation Enduring Freedom - Philippines. Operations have taken place mostly in the Sulu Archipelago, where terrorists and other groups are active. The majority of troops provide logistics. However, there are special forces troops that are training and assisting in combat operations against the terrorist groups. |
The British, for their part, lacked both a unified command and a clear strategy for winning. With the use of the Royal Navy, the British were able to capture coastal cities, but control of the countryside eluded them. A British sortie from Canada in 1777 ended with the disastrous surrender of a British army at Saratoga. With the coming in 1777 of General von Steuben, the training and discipline along Prussian lines began, and the Continental Army began to evolve into a modern force. France and Spain then entered the war against Great Britain as Allies of the US, ending its naval advantage and escalating the conflict into a world war. The Netherlands later joined France, and the British were outnumbered on land and sea in a world war, as they had no major allies apart from Indian tribes. |
When revolutionary France declared war on Great Britain in 1793, the United States sought to remain neutral, but the Jay Treaty, which was favorable to Great Britain, angered the French government, which viewed it as a violation of the 1778 Treaty of Alliance. French privateers began to seize U.S. vessels, which led to an undeclared "Quasi-War" between the two nations. Fought at sea from 1798 to 1800, the United States won a string of victories in the Caribbean. George Washington was called out of retirement to head a "provisional army" in case of invasion by France, but President John Adams managed to negotiate a truce, in which France agreed to terminate the prior alliance and cease its attacks. |
In the Treaty of Paris after the Revolution, the British had ceded the lands between the Appalachian Mountains and the Mississippi River to the United States, without consulting the Shawnee, Cherokee, Choctaw and other smaller tribes who lived there. Because many of the tribes had fought as allies of the British, the United States compelled tribal leaders to sign away lands in postwar treaties, and began dividing these lands for settlement. This provoked a war in the Northwest Territory in which the U.S. forces performed poorly; the Battle of the Wabash in 1791 was the most severe defeat ever suffered by the United States at the hands of American Indians. President Washington dispatched a newly trained army to the region, which decisively defeated the Indian confederacy at the Battle of Fallen Timbers in 1794. |
Sectional tensions had long existed between the states located north of the Mason–Dixon line and those south of it, primarily centered on the "peculiar institution" of slavery and the ability of states to overrule the decisions of the national government. During the 1840s and 1850s, conflicts between the two sides became progressively more violent. After the election of Abraham Lincoln in 1860 (who southerners thought would work to end slavery) states in the South seceded from the United States, beginning with South Carolina in late 1860. On April 12, 1861, forces of the South (known as the Confederate States of America or simply the Confederacy) opened fire on Fort Sumter, whose garrison was loyal to the Union. |
The Spanish–American War was a short decisive war marked by quick, overwhelming American victories at sea and on land against Spain. The Navy was well-prepared and won laurels, even as politicians tried (and failed) to have it redeployed to defend East Coast cities against potential threats from the feeble Spanish fleet. The Army performed well in combat in Cuba. However, it was too oriented to small posts in the West and not as well-prepared for an overseas conflict. It relied on volunteers and state militia units, which faced logistical, training and food problems in the staging areas in Florida. The United States freed Cuba (after an occupation by the U.S. Army). By the peace treaty Spain ceded to the United States its colonies of Puerto Rico, Guam, and the Philippines. The Navy set up coaling stations there and in Hawaii (which voluntarily joined the U.S. in 1898). The U.S. Navy now had a major forward presence across the Pacific and (with the lease of Guantánamo Bay Naval Base in Cuba) a major base in the Caribbean guarding the approaches to the Gulf Coast and the Panama Canal. |
The Philippine–American War (1899–1902) was an armed conflict between a group of Filipino revolutionaries and the American forces following the ceding of the Philippines to the United States after the defeat of Spanish forces in the Battle of Manila. The Army sent in 100,000 soldiers (mostly from the National Guard) under General Elwell Otis. Defeated in the field and losing its capital in March 1899, the poorly armed and poorly led rebels broke into armed bands. The insurgency collapsed in March 1901 when the leader Emilio Aguinaldo was captured by General Frederick Funston and his Macabebe allies. Casualties included 1,037 Americans killed in action and 3,340 who died from disease; 20,000 rebels were killed. |
The loss of eight battleships and 2,403 Americans at Pearl Harbor forced the U.S. to rely on its remaining aircraft carriers, which won a major victory over Japan at Midway just six months into the war, and on its growing submarine fleet. The Navy and Marine Corps followed this up with an island hopping campaign across the central and south Pacific in 1943–45, reaching the outskirts of Japan in the Battle of Okinawa. During 1942 and 1943, the U.S. deployed millions of men and thousands of planes and tanks to the UK, beginning with the strategic bombing of Nazi Germany and occupied Europe and leading up to the Allied invasions of occupied North Africa in November 1942, Sicily and Italy in 1943, France in 1944, and the invasion of Germany in 1945, parallel with the Soviet invasion from the east. That led to the surrender of Nazi Germany in May 1945. In the Pacific, the U.S. experienced much success in naval campaigns during 1944, but bloody battles at Iwo Jima and Okinawa in 1945 led the U.S. to look for a way to end the war with minimal loss of American lives. The U.S. used atomic bombs on Hiroshima and Nagasaki to destroy the Japanese war effort and to shock the Japanese leadership, which quickly caused the surrender of Japan. |
The Korean War was a conflict between the United States and its United Nations allies and the communist powers under influence of the Soviet Union (also a UN member nation) and the People's Republic of China (which later also gained UN membership). The principal combatants were North and South Korea. Principal allies of South Korea included the United States, Canada, Australia, the United Kingdom, although many other nations sent troops under the aegis of the United Nations. Allies of North Korea included the People's Republic of China, which supplied military forces, and the Soviet Union, which supplied combat advisors and aircraft pilots, as well as arms, for the Chinese and North Korean troops. |
The war started badly for the US and UN. North Korean forces struck massively in the summer of 1950 and nearly drove the outnumbered US and ROK defenders into the sea. However the United Nations intervened, naming Douglas MacArthur commander of its forces, and UN-US-ROK forces held a perimeter around Pusan, gaining time for reinforcement. MacArthur, in a bold but risky move, ordered an amphibious invasion well behind the front lines at Inchon, cutting off and routing the North Koreans and quickly crossing the 38th Parallel into North Korea. As UN forces continued to advance toward the Yalu River on the border with Communist China, the Chinese crossed the Yalu River in October and launched a series of surprise attacks that sent the UN forces reeling back across the 38th Parallel. Truman originally wanted a Rollback strategy to unify Korea; after the Chinese successes he settled for a Containment policy to split the country. MacArthur argued for rollback but was fired by President Harry Truman after disputes over the conduct of the war. Peace negotiations dragged on for two years until President Dwight D. Eisenhower threatened China with nuclear weapons; an armistice was quickly reached with the two Koreas remaining divided at the 38th parallel. North and South Korea are still today in a state of war, having never signed a peace treaty, and American forces remain stationed in South Korea as part of American foreign policy. |
Fighting on one side was a coalition of forces including the Republic of Vietnam (South Vietnam or the "RVN"), the United States, supplemented by South Korea, Thailand, Australia, New Zealand, and the Philippines. The allies fought against the North Vietnamese Army (NVA) as well as the National Liberation Front (NLF, also known as Viet communists Viet Cong), or "VC", a guerrilla force within South Vietnam. The NVA received substantial military and economic aid from the Soviet Union and China, turning Vietnam into a proxy war. |
The military history of the American side of the war involved different strategies over the years. The bombing campaigns of the Air Force were tightly controlled by the White House for political reasons, and until 1972 avoided the main Northern cities of Hanoi and Haiphong and concentrated on bombing jungle supply trails, especially the Ho Chi Minh Trail. The most controversial Army commander was William Westmoreland whose strategy involved systematic defeat of all enemy forces in the field, despite heavy American casualties that alienated public opinion back home. |
In 1983 fighting between Palestinian refugees and Lebanese factions reignited that nation's long-running civil war. A UN agreement brought an international force of peacekeepers to occupy Beirut and guarantee security. US Marines landed in August 1982 along with Italian and French forces. On October 23, 1983, a suicide bomber driving a truck filled with 6 tons of TNT crashed through a fence and destroyed the Marine barracks, killing 241 Marines; seconds later, a second bomber leveled a French barracks, killing 58. Subsequently the US Navy engaged in bombing of militia positions inside Lebanon. While US President Ronald Reagan was initially defiant, political pressure at home eventually forced the withdrawal of the Marines in February 1984. |
However, the battle was one-sided almost from the beginning. The reasons for this are the subject of continuing study by military strategists and academics. There is general agreement that US technological superiority was a crucial factor but the speed and scale of the Iraqi collapse has also been attributed to poor strategic and tactical leadership and low morale among Iraqi troops, which resulted from a history of incompetent leadership. After devastating initial strikes against Iraqi air defenses and command and control facilities on 17 January 1991, coalition forces achieved total air superiority almost immediately. The Iraqi air force was destroyed within a few days, with some planes fleeing to Iran, where they were interned for the duration of the conflict. The overwhelming technological advantages of the US, such as stealth aircraft and infrared sights, quickly turned the air war into a "turkey shoot". The heat signature of any tank which started its engine made an easy target. Air defense radars were quickly destroyed by radar-seeking missiles fired from wild weasel aircraft. Grainy video clips, shot from the nose cameras of missiles as they aimed at impossibly small targets, were a staple of US news coverage and revealed to the world a new kind of war, compared by some to a video game. Over 6 weeks of relentless pounding by planes and helicopters, the Iraqi army was almost completely beaten but did not retreat, under orders from Iraqi President Saddam Hussein, and by the time the ground forces invaded on 24 February, many Iraqi troops quickly surrendered to forces much smaller than their own; in one instance, Iraqi forces attempted to surrender to a television camera crew that was advancing with coalition forces. |
After just 100 hours of ground combat, and with all of Kuwait and much of southern Iraq under coalition control, US President George H. W. Bush ordered a cease-fire and negotiations began resulting in an agreement for cessation of hostilities. Some US politicians were disappointed by this move, believing Bush should have pressed on to Baghdad and removed Hussein from power; there is little doubt that coalition forces could have accomplished this if they had desired. Still, the political ramifications of removing Hussein would have broadened the scope of the conflict greatly, and many coalition nations refused to participate in such an action, believing it would create a power vacuum and destabilize the region. |
The War on Terrorism is a global effort by the governments of several countries (primarily the United States and its principal allies) to neutralize international terrorist groups (primarily Islamic Extremist terrorist groups, including al-Qaeda) and ensure that countries considered by the US and some of its allies to be Rogue Nations no longer support terrorist activities. It has been adopted primarily as a response to the September 11, 2001 attacks on the United States. Since 2001, terrorist motivated attacks upon service members have occurred in Arkansas and Texas. |
After the lengthy Iraq disarmament crisis culminated with an American demand that Iraqi President Saddam Hussein leave Iraq, which was refused, a coalition led by the United States and the United Kingdom fought the Iraqi army in the 2003 invasion of Iraq. Approximately 250,000 United States troops, with support from 45,000 British, 2,000 Australian and 200 Polish combat forces, entered Iraq primarily through their staging area in Kuwait. (Turkey had refused to permit its territory to be used for an invasion from the north.) Coalition forces also supported Iraqi Kurdish militia, estimated to number upwards of 50,000. After approximately three weeks of fighting, Hussein and the Ba'ath Party were forcibly removed, followed by 9 years of military presence by the United States and the coalition fighting alongside the newly elected Iraqi government against various insurgent groups. |
As a result of the Libyan Civil War, the United Nations enacted United Nations Security Council Resolution 1973, which imposed a no-fly zone over Libya, and the protection of civilians from the forces of Muammar Gaddafi. The United States, along with Britain, France and several other nations, committed a coalition force against Gaddafi's forces. On 19 March, the first U.S. action was taken when 114 Tomahawk missiles launched by US and UK warships destroyed shoreline air defenses of the Gaddafi regime. The U.S. continued to play a major role in Operation Unified Protector, the NATO-directed mission that eventually incorporated all of the military coalition's actions in the theater. Throughout the conflict however, the U.S. maintained it was playing a supporting role only and was following the UN mandate to protect civilians, while the real conflict was between Gaddafi's loyalists and Libyan rebels fighting to depose him. During the conflict, American drones were also deployed. |
General George Washington (1732–99) proved an excellent organizer and administrator, who worked successfully with Congress and the state governors, selecting and mentoring his senior officers, supporting and training his troops, and maintaining an idealistic Republican Army. His biggest challenge was logistics, since neither Congress nor the states had the funding to provide adequately for the equipment, munitions, clothing, paychecks, or even the food supply of the soldiers. As a battlefield tactician Washington was often outmaneuvered by his British counterparts. As a strategist, however, he had a better idea of how to win the war than they did. The British sent four invasion armies. Washington's strategy forced the first army out of Boston in 1776, and was responsible for the surrender of the second and third armies at Saratoga (1777) and Yorktown (1781). He limited the British control to New York and a few places while keeping Patriot control of the great majority of the population. The Loyalists, on whom the British had relied too heavily, comprised about 20% of the population but never were well organized. As the war ended, Washington watched proudly as the final British army quietly sailed out of New York City in November 1783, taking the Loyalist leadership with them. Washington astonished the world when, instead of seizing power, he retired quietly to his farm in Virginia. |
The Berbers along the Barbary Coast (modern day Libya) sent pirates to capture merchant ships and hold the crews for ransom. The U.S. paid protection money until 1801, when President Thomas Jefferson refused to pay and sent in the Navy to challenge the Barbary States, the First Barbary War followed. After the U.S.S. Philadelphia was captured in 1803, Lieutenant Stephen Decatur led a raid which successfully burned the captured ship, preventing Tripoli from using or selling it. In 1805, after William Eaton captured the city of Derna, Tripoli agreed to a peace treaty. The other Barbary states continued to raid U.S. shipping, until the Second Barbary War in 1815 ended the practice. |
The American Civil War caught both sides unprepared. The Confederacy hoped to win by getting Britain and France to intervene, or else by wearing down the North's willingness to fight. The U.S. sought a quick victory focused on capturing the Confederate capital at Richmond, Virginia. The Confederates under Robert E. Lee tenaciously defended their capital until the very end. The war spilled across the continent, and even to the high seas. Most of the material and personnel of the South were used up, while the North prospered. |
The Navy was modernized in the 1880s, and by the 1890s had adopted the naval power strategy of Captain Alfred Thayer Mahan—as indeed did every major navy. The old sailing ships were replaced by modern steel battleships, bringing them in line with the navies of Britain and Germany. In 1907, most of the Navy's battleships, with several support vessels, dubbed the Great White Fleet, were featured in a 14-month circumnavigation of the world. Ordered by President Theodore Roosevelt, it was a mission designed to demonstrate the Navy's capability to extend to the global theater. |
The Mexican Revolution involved a civil war with hundreds of thousands of deaths and large numbers fleeing combat zones. Tens of thousands fled to the U.S. President Wilson sent U.S. forces to occupy the Mexican city of Veracruz for six months in 1914. It was designed to show the U.S. was keenly interested in the civil war and would not tolerate attacks on Americans, especially the April 9, 1914, "Tampico Affair", which involved the arrest of American sailors by soldiers of the regime of Mexican President Victoriano Huerta. In early 1916 Pancho Villa a Mexican general ordered 500 soldiers on a murderous raid on the American city of Columbus New Mexico, with the goal of robbing banks to fund his army. The German Secret Service encouraged Pancho Villa in his attacks to involve the United States in an intervention in Mexico which would distract the United States from its growing involvement in the war and divert aid from Europe to support the intervention. Wilson called up the state militias (National Guard) and sent them and the U.S. Army under General John J. Pershing to punish Villa in the Pancho Villa Expedition. Villa fled, with the Americans in pursuit deep into Mexico, thereby arousing Mexican nationalism. By early 1917 President Venustiano Carranza had contained Villa and secured the border, so Wilson ordered Pershing to withdraw. |
After the costly U.S. involvement in World War I, isolationism grew within the nation. Congress refused membership in the League of Nations, and in response to the growing turmoil in Europe and Asia, the gradually more restrictive Neutrality Acts were passed, which were intended to prevent the U.S. from supporting either side in a war. President Franklin D. Roosevelt sought to support Britain, however, and in 1940 signed the Lend-Lease Act, which permitted an expansion of the "cash and carry" arms trade to develop with Britain, which controlled the Atlantic sea lanes. |
World War II holds a special place in the American psyche as the country's greatest triumph, and the U.S. military personnel of World War II are frequently referred to as "the Greatest Generation." Over 16 million served (about 11% of the population), and over 400,000 died during the war. The U.S. emerged as one of the two undisputed superpowers along with the Soviet Union, and unlike the Soviet Union, the U.S. homeland was virtually untouched by the ravages of war. During and following World War II, the United States and Britain developed an increasingly strong defense and intelligence relationship. Manifestations of this include extensive basing of U.S. forces in the UK, shared intelligence, shared military technology (e.g. nuclear technology), and shared procurement. |
The U.S. framed the war as part of its policy of containment of Communism in south Asia, but American forces were frustrated by an inability to engage the enemy in decisive battles, corruption and incompetence in the Army of the Republic of Vietnam, and ever increasing protests at home. The Tet Offensive in 1968, although a major military defeat for the NLF with half their forces eliminated, marked the psychological turning point in the war. With President Richard M. Nixon opposed to containment and more interested in achieving détente with both the Soviet Union and China, American policy shifted to "Vietnamization," – providing very large supplies of arms and letting the Vietnamese fight it out themselves. After more than 57,000 dead and many more wounded, American forces withdrew in 1973 with no clear victory, and in 1975 South Vietnam was finally conquered by communist North Vietnam and unified. |
Ongoing political tensions between Great Britain and the thirteen colonies reached a crisis in 1774 when the British placed the province of Massachusetts under martial law after the Patriots protested taxes they regarded as a violation of their constitutional rights as Englishmen. When shooting began at Lexington and Concord in April 1775, militia units from across New England rushed to Boston and bottled up the British in the city. The Continental Congress appointed George Washington as commander-in-chief of the newly created Continental Army, which was augmented throughout the war by colonial militia. He drove the British out of Boston but in late summer 1776 they returned to New York and nearly captured Washington's army. Meanwhile, the revolutionaries expelled British officials from the 13 states, and declared themselves an independent nation on July 4, 1776. |
Following the American Revolutionary War, the United States faced potential military conflict on the high seas as well as on the western frontier. The United States was a minor military power during this time, having only a modest army, Marine corps, and navy. A traditional distrust of standing armies, combined with faith in the abilities of local militia, precluded the development of well-trained units and a professional officer corps. Jeffersonian leaders preferred a small army and navy, fearing that a large military establishment would involve the United States in excessive foreign wars, and potentially allow a domestic tyrant to seize power. |
After the Civil War, population expansion, railroad construction, and the disappearance of the buffalo herds heightened military tensions on the Great Plains. Several tribes, especially the Sioux and Comanche, fiercely resisted confinement to reservations. The main role of the Army was to keep indigenous peoples on reservations and to end their wars against settlers and each other, William Tecumseh Sherman and Philip Sheridan were in charge. A famous victory for the Plains Nations was the Battle of the Little Big Horn in 1876, when Col. George Armstrong Custer and two hundred plus members of the 7th Cavalry were killed by a force consisting of Native Americans from the Lakota, Northern Cheyenne, and Arapaho nations. The last significant conflict came in 1891. |
Rear Admiral Bradley A. Fiske was at the vanguard of new technology in naval guns and gunnery, thanks to his innovations in fire control 1890–1910. He immediately grasped the potential for air power, and called for the development of a torpedo plane. Fiske, as aide for operations in 1913–15 to Assistant Secretary Franklin D. Roosevelt, proposed a radical reorganization of the Navy to make it a war-fighting instrument. Fiske wanted to centralize authority in a chief of naval operations and an expert staff that would develop new strategies, oversee the construction of a larger fleet, coordinate war planning including force structure, mobilization plans, and industrial base, and ensure that the US Navy possessed the best possible war machines. Eventually, the Navy adopted his reforms and by 1915 started to reorganize for possible involvement in the World War then underway. |
By summer 1918, a million American soldiers, or "doughboys" as they were often called, of the American Expeditionary Forces were in Europe under the command of John J. Pershing, with 25,000 more arriving every week. The failure of Germany's spring offensive exhausted its reserves and they were unable to launch new offensives. The German Navy and home front then revolted and a new German government signed a conditional surrender, the Armistice, ending the war against the western front on November 11, 1918. |
Starting in 1940 (18 months before Pearl Harbor), the nation mobilized, giving high priority to air power. American involvement in World War II in 1940–41 was limited to providing war material and financial support to Britain, the Soviet Union, and the Republic of China. The U.S. entered officially on 8 December 1941 following the Japanese attack on Pearl Harbor, Hawaii. Japanese forces soon seized American, Dutch, and British possessions across the Pacific and Southeast Asia, except for Australia, which became a main American forward base along with Hawaii. |
The Vietnam War was a war fought between 1959 and 1975 on the ground in South Vietnam and bordering areas of Cambodia and Laos (see Secret War) and in the strategic bombing (see Operation Rolling Thunder) of North Vietnam. American advisors came in the late 1950s to help the RVN (Republic of Vietnam) combat Communist insurgents known as "Viet Cong." Major American military involvement began in 1964, after Congress provided President Lyndon B. Johnson with blanket approval for presidential use of force in the Gulf of Tonkin Resolution. |
Before the war, many observers believed the US and its allies could win but might suffer substantial casualties (certainly more than any conflict since Vietnam), and that the tank battles across the harsh desert might rival those of North Africa during World War II. After nearly 50 years of proxy wars, and constant fears of another war in Europe between NATO and the Warsaw Pact, some thought the Persian Gulf War might finally answer the question of which military philosophy would have reigned supreme. Iraqi forces were battle-hardened after 8 years of war with Iran, and they were well equipped with late model Soviet tanks and jet fighters, but the antiaircraft weapons were crippled; in comparison, the US had no large-scale combat experience since its withdrawal from Vietnam nearly 20 years earlier, and major changes in US doctrine, equipment and technology since then had never been tested under fire. |
With the emergence of ISIL and its capture of large areas of Iraq and Syria, a number of crises resulted that sparked international attention. ISIL had perpetrated sectarian killings and war crimes in both Iraq and Syria. Gains made in the Iraq war were rolled back as Iraqi army units abandoned their posts. Cities were taken over by the terrorist group which enforced its brand of Sharia law. The kidnapping and decapitation of numerous Western journalists and aid-workers also garnered interest and outrage among Western powers. The US intervened with airstrikes in Iraq over ISIL held territories and assets in August, and in September a coalition of US and Middle Eastern powers initiated a bombing campaign in Syria aimed at degrading and destroying ISIL and Al-Nusra-held territory. |
Groups that emerged from the American psychedelic scene about the same time included Iron Butterfly, MC5, Blue Cheer and Vanilla Fudge. San Francisco band Blue Cheer released a crude and distorted cover of Eddie Cochran's classic "Summertime Blues", from their 1968 debut album Vincebus Eruptum, that outlined much of the later hard rock and heavy metal sound. The same month, Steppenwolf released its self-titled debut album, including "Born to Be Wild", which contained the first lyrical reference to heavy metal and helped popularise the style when it was used in the film Easy Rider (1969). Iron Butterfly's In-A-Gadda-Da-Vida (1968), with its 17-minute-long title track, using organs and with a lengthy drum solo, also prefigured later elements of the sound. |
From outside the United Kingdom and the United States, the Canadian trio Rush released three distinctively hard rock albums in 1974–75 (Rush, Fly by Night and Caress of Steel) before moving toward a more progressive sound with the 1976 album 2112. The Irish band Thin Lizzy, which had formed in the late 1960s, made their most substantial commercial breakthrough in 1976 with the hard rock album Jailbreak and their worldwide hit "The Boys Are Back in Town", which reached number 8 in the UK and number 12 in the US. Their style, consisting of two duelling guitarists often playing leads in harmony, proved itself to be a large influence on later bands. They reached their commercial, and arguably their artistic peak with Black Rose: A Rock Legend (1979). The arrival of Scorpions from Germany marked the geographical expansion of the subgenre. Australian-formed AC/DC, with a stripped back, riff heavy and abrasive style that also appealed to the punk generation, began to gain international attention from 1976, culminating in the release of their multi-platinum albums Let There Be Rock (1977) and Highway to Hell (1979). Also influenced by a punk ethos were heavy metal bands like Motörhead, while Judas Priest abandoned the remaining elements of the blues in their music, further differentiating the hard rock and heavy metal styles and helping to create the New Wave of British Heavy Metal which was pursued by bands like Iron Maiden, Saxon and Venom. |
Bon Jovi's third album, Slippery When Wet (1986), mixed hard rock with a pop sensitivity and spent a total of 8 weeks at the top of the Billboard 200 album chart, selling 12 million copies in the US while becoming the first hard rock album to spawn three top 10 singles — two of which reached number one. The album has been credited with widening the audiences for the genre, particularly by appealing to women as well as the traditional male dominated audience, and opening the door to MTV and commercial success for other bands at the end of the decade. The anthemic The Final Countdown (1986) by Swedish group Europe was an international hit, reaching number eight on the US charts while hitting the top 10 in nine other countries. This era also saw more glam-infused American hard rock bands come to the forefront, with both Poison and Cinderella releasing their multi-platinum début albums in 1986. Van Halen released 5150 (1986), their first album with Sammy Hagar on lead vocals, which was number one in the US for three weeks and sold over 6 million copies. By the second half of the decade, hard rock had become the most reliable form of commercial popular music in the United States. |
Some established acts continued to enjoy commercial success, such as Aerosmith, with their number one multi-platinum albums: Get a Grip (1993), which produced four Top 40 singles and became the band's best-selling album worldwide (going on to sell over 10 million copies), and Nine Lives (1997). In 1998, Aerosmith released the number one hit "I Don't Want to Miss a Thing", which remains the only single by a hard rock band to debut at number one. AC/DC produced the double platinum Ballbreaker (1995). Bon Jovi appealed to their hard rock audience with songs such as "Keep the Faith" (1992), but also achieved success in adult contemporary radio, with the Top 10 ballads "Bed of Roses" (1993) and "Always" (1994). Bon Jovi's 1995 album These Days was a bigger hit in Europe than it was in the United States, spawning four Top 10 singles on the UK Singles Chart. Metallica's Load (1996) and ReLoad (1997) each sold in excess of 4 million copies in the US and saw the band develop a more melodic and blues rock sound. As the initial impetus of grunge bands faltered in the middle years of the decade, post-grunge bands emerged. They emulated the attitudes and music of grunge, particularly thick, distorted guitars, but with a more radio-friendly commercially oriented sound that drew more directly on traditional hard rock. Among the most successful acts were the Foo Fighters, Candlebox, Live, Collective Soul, Australia's Silverchair and England's Bush, who all cemented post-grunge as one of the most commercially viable subgenres by the late 1990s. Similarly, some post-Britpop bands that followed in the wake of Oasis, including Feeder and Stereophonics, adopted a hard rock or "pop-metal" sound. |
Hard rock developed into a major form of popular music in the 1970s, with bands such as Led Zeppelin, The Who, Deep Purple, Aerosmith, AC/DC and Van Halen. During the 1980s, some hard rock bands moved away from their hard rock roots and more towards pop rock, while others began to return to a hard rock sound. Established bands made a comeback in the mid-1980s and it reached a commercial peak in the 1980s, with glam metal bands like Bon Jovi and Def Leppard and the rawer sounds of Guns N' Roses, which followed up with great success in the later part of that decade. Hard rock began losing popularity with the commercial success of grunge and later Britpop in the 1990s. |
The roots of hard rock can be traced back to the 1950s, particularly electric blues, which laid the foundations for key elements such as a rough declamatory vocal style, heavy guitar riffs, string-bending blues-scale guitar solos, strong beat, thick riff-laden texture, and posturing performances. Electric blues guitarists began experimenting with hard rock elements such as driving rhythms, distorted guitar solos and power chords in the 1950s, evident in the work of Memphis blues guitarists such as Joe Hill Louis, Willie Johnson, and particularly Pat Hare, who captured a "grittier, nastier, more ferocious electric guitar sound" on records such as James Cotton's "Cotton Crop Blues" (1954). Other antecedents include Link Wray's instrumental "Rumble" in 1958, and the surf rock instrumentals of Dick Dale, such as "Let's Go Trippin'" (1961) and "Misirlou" (1962). |
In the early 1970s the Rolling Stones developed their hard rock sound with Exile on Main St. (1972). Initially receiving mixed reviews, according to critic Steve Erlewine it is now "generally regarded as the Rolling Stones' finest album". They continued to pursue the riff-heavy sound on albums including It's Only Rock 'n' Roll (1974) and Black and Blue (1976). Led Zeppelin began to mix elements of world and folk music into their hard rock from Led Zeppelin III (1970) and Led Zeppelin IV (1971). The latter included the track "Stairway to Heaven", which would become the most played song in the history of album-oriented radio. Deep Purple continued to define hard rock, particularly with their album Machine Head (1972), which included the tracks "Highway Star" and "Smoke on the Water". In 1975 guitarist Ritchie Blackmore left, going on to form Rainbow and after the break-up of the band the next year, vocalist David Coverdale formed Whitesnake. 1970 saw The Who release Live at Leeds, often seen as the archetypal hard rock live album, and the following year they released their highly acclaimed album Who's Next, which mixed heavy rock with extensive use of synthesizers. Subsequent albums, including Quadrophenia (1973), built on this sound before Who Are You (1978), their last album before the death of pioneering rock drummer Keith Moon later that year. |
The opening years of the 1980s saw a number of changes in personnel and direction of established hard rock acts, including the deaths of Bon Scott, the lead singer of AC/DC, and John Bonham, drummer with Led Zeppelin. Whereas Zeppelin broke up almost immediately afterwards, AC/DC pressed on, recording the album Back in Black (1980) with their new lead singer, Brian Johnson. It became the fifth-highest-selling album of all time in the US and the second-highest-selling album in the world. Black Sabbath had split with original singer Ozzy Osbourne in 1979 and replaced him with Ronnie James Dio, formerly of Rainbow, giving the band a new sound and a period of creativity and popularity beginning with Heaven and Hell (1980). Osbourne embarked on a solo career with Blizzard of Ozz (1980), featuring American guitarist Randy Rhoads. Some bands, such as Queen, moved away from their hard rock roots and more towards pop rock, while others, including Rush with Moving Pictures (1981), began to return to a hard rock sound. The creation of thrash metal, which mixed heavy metal with elements of hardcore punk from about 1982, particularly by Metallica, Anthrax, Megadeth and Slayer, helped to create extreme metal and further remove the style from hard rock, although a number of these bands or their members would continue to record some songs closer to a hard rock sound. Kiss moved away from their hard rock roots toward pop metal: firstly removing their makeup in 1983 for their Lick It Up album, and then adopting the visual and sound of glam metal for their 1984 release, Animalize, both of which marked a return to commercial success. Pat Benatar was one of the first women to achieve commercial success in hard rock, with three successive Top 5 albums between 1980 and 1982. |
Hard rock entered the 1990s as one of the dominant forms of commercial music. The multi-platinum releases of AC/DC's The Razors Edge (1990), Guns N' Roses' Use Your Illusion I and Use Your Illusion II (both in 1991), Ozzy Osbourne's No More Tears (1991), and Van Halen's For Unlawful Carnal Knowledge (1991) showcased this popularity. Additionally, The Black Crowes released their debut album, Shake Your Money Maker (1990), which contained a bluesy classic rock sound and sold five million copies. In 1992, Def Leppard followed up 1987's Hysteria with Adrenalize, which went multi-platinum, spawned four Top 40 singles and held the number one spot on the US album chart for five weeks. |
The term "retro-metal" has been applied to such bands as Texas based The Sword, California's High on Fire, Sweden's Witchcraft and Australia's Wolfmother. Wolfmother's self-titled 2005 debut album combined elements of the sounds of Deep Purple and Led Zeppelin. Fellow Australians Airbourne's début album Runnin' Wild (2007) followed in the hard riffing tradition of AC/DC. England's The Darkness' Permission to Land (2003), described as an "eerily realistic simulation of '80s metal and '70s glam", topped the UK charts, going quintuple platinum. The follow-up, One Way Ticket to Hell... and Back (2005), reached number 11, before the band broke up in 2006. Los Angeles band Steel Panther managed to gain a following by sending up 80s glam metal. A more serious attempt to revive glam metal was made by bands of the sleaze metal movement in Sweden, including Vains of Jenna, Hardcore Superstar and Crashdïet. |
In the 1960s, American and British blues and rock bands began to modify rock and roll by adding harder sounds, heavier guitar riffs, bombastic drumming, and louder vocals, from electric blues. Early forms of hard rock can be heard in the work of Chicago blues musicians Elmore James, Muddy Waters, and Howlin' Wolf, The Kingsmen's version of "Louie Louie" (1963) which made it a garage rock standard, and the songs of rhythm and blues influenced British Invasion acts, including "You Really Got Me" by The Kinks (1964), "My Generation" by The Who (1965), "Shapes of Things" (1966) by The Yardbirds and "(I Can't Get No) Satisfaction" (1965) by The Rolling Stones. From the late 1960s, it became common to divide mainstream rock music that emerged from psychedelia into soft and hard rock. Soft rock was often derived from folk rock, using acoustic instruments and putting more emphasis on melody and harmonies. In contrast, hard rock was most often derived from blues rock and was played louder and with more intensity. |
Emerging British acts included Free, who released their signature song "All Right Now" (1970), which has received extensive radio airplay in both the UK and US. After the breakup of the band in 1973, vocalist Paul Rodgers joined supergroup Bad Company, whose eponymous first album (1974) was an international hit. The mixture of hard rock and progressive rock, evident in the works of Deep Purple, was pursued more directly by bands like Uriah Heep and Argent. Scottish band Nazareth released their self-titled début album in 1971, producing a blend of hard rock and pop that would culminate in their best selling, Hair of the Dog (1975), which contained the proto-power ballad "Love Hurts". Having enjoyed some national success in the early 1970s, Queen, after the release of Sheer Heart Attack (1974) and A Night at the Opera (1975), gained international recognition with a sound that used layered vocals and guitars and mixed hard rock with heavy metal, progressive rock, and even opera. The latter featured the single "Bohemian Rhapsody", which stayed at number one in the UK charts for nine weeks. |
Often categorised with the New Wave of British Heavy Metal, in 1981 Def Leppard released their second album High 'n' Dry, mixing glam-rock with heavy metal, and helping to define the sound of hard rock for the decade. The follow-up Pyromania (1983), reached number two on the American charts and the singles "Photograph", "Rock of Ages" and "Foolin'", helped by the emergence of MTV, all reached the Top 40. It was widely emulated, particularly by the emerging Californian glam metal scene. This was followed by US acts like Mötley Crüe, with their albums Too Fast for Love (1981) and Shout at the Devil (1983) and, as the style grew, the arrival of bands such as Ratt, White Lion, Twisted Sister and Quiet Riot. Quiet Riot's album Metal Health (1983) was the first glam metal album, and arguably the first heavy metal album of any kind, to reach number one in the Billboard music charts and helped open the doors for mainstream success by subsequent bands. |
While these few hard rock bands managed to maintain success and popularity in the early part of the decade, alternative forms of hard rock achieved mainstream success in the form of grunge in the US and Britpop in the UK. This was particularly evident after the success of Nirvana's Nevermind (1991), which combined elements of hardcore punk and heavy metal into a "dirty" sound that made use of heavy guitar distortion, fuzz and feedback, along with darker lyrical themes than their "hair band" predecessors. Although most grunge bands had a sound that sharply contrasted mainstream hard rock, several, including Pearl Jam, Alice in Chains, Mother Love Bone and Soundgarden, were more strongly influenced by 1970s and 1980s rock and metal, while Stone Temple Pilots managed to turn alternative rock into a form of stadium rock. However, all grunge bands shunned the macho, anthemic and fashion-focused aesthetics particularly associated with glam metal. In the UK, Oasis were unusual among the Britpop bands of the mid-1990s in incorporating a hard rock sound. |
Although Foo Fighters continued to be one of the most successful rock acts, with albums like In Your Honor (2005) reaching number two in the US and UK, many of the first wave of post-grunge bands began to fade in popularity. Acts like Creed, Staind, Puddle of Mudd and Nickelback took the genre into the 2000s with considerable commercial success, abandoning most of the angst and anger of the original movement for more conventional anthems, narratives and romantic songs. They were followed in this vein by new acts including Shinedown and Seether. Acts with more conventional hard rock sounds included Andrew W.K., Beautiful Creatures and Buckcherry, whose breakthrough album 15 (2006) went platinum and spawned the single "Sorry" (2007), which made the Top 10 of the Billboard 100. These were joined by bands with hard rock leanings that emerged in the mid-2000s from the garage rock or post punk revival, including Black Rebel Motorcycle Club and Kings of Leon, and Queens of the Stone Age from the US, Three Days Grace from Canada, Jet from Australia and The Datsuns from New Zealand. In 2009 Them Crooked Vultures, a supergroup that brought together Foo Fighters' Dave Grohl, Queens of the Stone Age's Josh Homme and Led Zeppelin bass player John Paul Jones attracted attention as a live act and released a self-titled debut album that reached the top 20 in the US and UK and the top ten in several other countries. |
Hard rock is a form of loud, aggressive rock music. The electric guitar is often emphasised, used with distortion and other effects, both as a rhythm instrument using repetitive riffs with a varying degree of complexity, and as a solo lead instrument. Drumming characteristically focuses on driving rhythms, strong bass drum and a backbeat on snare, sometimes using cymbals for emphasis. The bass guitar works in conjunction with the drums, occasionally playing riffs, but usually providing a backing for the rhythm and lead guitars. Vocals are often growling, raspy, or involve screaming or wailing, sometimes in a high range, or even falsetto voice. |
Blues rock acts that pioneered the sound included Cream, The Jimi Hendrix Experience, and The Jeff Beck Group. Cream, in songs like "I Feel Free" (1966) combined blues rock with pop and psychedelia, particularly in the riffs and guitar solos of Eric Clapton. Jimi Hendrix produced a form of blues-influenced psychedelic rock, which combined elements of jazz, blues and rock and roll. From 1967 Jeff Beck brought lead guitar to new heights of technical virtuosity and moved blues rock in the direction of heavy rock with his band, The Jeff Beck Group. Dave Davies of The Kinks, Keith Richards of The Rolling Stones, Pete Townshend of The Who, Hendrix, Clapton and Beck all pioneered the use of new guitar effects like phasing, feedback and distortion. The Beatles began producing songs in the new hard rock style beginning with the White Album in 1968 and, with the track "Helter Skelter", attempted to create a greater level of noise than the Who. Stephen Thomas Erlewine of AllMusic has described the "proto-metal roar" of "Helter Skelter," while Ian MacDonald argued that "their attempts at emulating the heavy style were without exception embarrassing." |
In the United States, macabre-rock pioneer Alice Cooper achieved mainstream success with the top ten album School's Out (1972). In the following year blues rockers ZZ Top released their classic album Tres Hombres and Aerosmith produced their eponymous début, as did Southern rockers Lynyrd Skynyrd and proto-punk outfit New York Dolls, demonstrating the diverse directions being pursued in the genre. Montrose, including the instrumental talent of Ronnie Montrose and vocals of Sammy Hagar and arguably the first all American hard rock band to challenge the British dominance of the genre, released their first album in 1973. Kiss built on the theatrics of Alice Cooper and the look of the New York Dolls to produce a unique band persona, achieving their commercial breakthrough with the double live album Alive! in 1975 and helping to take hard rock into the stadium rock era. In the mid-1970s Aerosmith achieved their commercial and artistic breakthrough with Toys in the Attic (1975), which reached number 11 in the American album chart, and Rocks (1976), which peaked at number three. Blue Öyster Cult, formed in the late 60s, picked up on some of the elements introduced by Black Sabbath with their breakthrough live gold album On Your Feet or on Your Knees (1975), followed by their first platinum album, Agents of Fortune (1976), containing the hit single "(Don't Fear) The Reaper", which reached number 12 on the Billboard charts. Journey released their eponymous debut in 1975 and the next year Boston released their highly successful début album. In the same year, hard rock bands featuring women saw commercial success as Heart released Dreamboat Annie and The Runaways débuted with their self-titled album. While Heart had a more folk-oriented hard rock sound, the Runaways leaned more towards a mix of punk-influenced music and hard rock. The Amboy Dukes, having emerged from the Detroit garage rock scene and most famous for their Top 20 psychedelic hit "Journey to the Center of the Mind" (1968), were dissolved by their guitarist Ted Nugent, who embarked on a solo career that resulted in four successive multi-platinum albums between Ted Nugent (1975) and his best selling Double Live Gonzo (1978). |
Established bands made something of a comeback in the mid-1980s. After an 8-year separation, Deep Purple returned with the classic Machine Head line-up to produce Perfect Strangers (1984), which reached number five in the UK, hit the top five in five other countries, and was a platinum-seller in the US. After somewhat slower sales of its fourth album, Fair Warning, Van Halen rebounded with the Top 3 album Diver Down in 1982, then reached their commercial pinnacle with 1984. It reached number two on the Billboard album chart and provided the track "Jump", which reached number one on the singles chart and remained there for several weeks. Heart, after floundering during the first half of the decade, made a comeback with their eponymous ninth studio album which hit number one and contained four Top 10 singles including their first number one hit. The new medium of video channels was used with considerable success by bands formed in previous decades. Among the first were ZZ Top, who mixed hard blues rock with new wave music to produce a series of highly successful singles, beginning with "Gimme All Your Lovin'" (1983), which helped their albums Eliminator (1983) and Afterburner (1985) achieve diamond and multi-platinum status respectively. Others found renewed success in the singles charts with power ballads, including REO Speedwagon with "Keep on Loving You" (1980) and "Can't Fight This Feeling" (1984), Journey with "Don't Stop Believin'" (1981) and "Open Arms" (1982), Foreigner's "I Want to Know What Love Is", Scorpions' "Still Loving You" (both from 1984), Heart’s "What About Love" (1985) and "These Dreams" (1986), and Boston's "Amanda" (1986). |
In the new commercial climate glam metal bands like Europe, Ratt, White Lion and Cinderella broke up, Whitesnake went on hiatus in 1991, and while many of these bands would re-unite again in the late 1990s or early 2000s, they never reached the commercial success they saw in the 1980s or early 1990s. Other bands such as Mötley Crüe and Poison saw personnel changes which impacted those bands' commercial viability during the decade. In 1995 Van Halen released Balance, a multi-platinum seller that would be the band's last with Sammy Hagar on vocals. In 1996 David Lee Roth returned briefly and his replacement, former Extreme singer Gary Cherone, was fired soon after the release of the commercially unsuccessful 1998 album Van Halen III and Van Halen would not tour or record again until 2004. Guns N' Roses' original lineup was whittled away throughout the decade. Drummer Steven Adler was fired in 1990, guitarist Izzy Stradlin left in late 1991 after recording Use Your Illusion I and II with the band. Tensions between the other band members and lead singer Axl Rose continued after the release of the 1993 covers album The Spaghetti Incident? Guitarist Slash left in 1996, followed by bassist Duff McKagan in 1997. Axl Rose, the only original member, worked with a constantly changing lineup in recording an album that would take over fifteen years to complete. |
In the late 1960s, the term heavy metal was used interchangeably with hard rock, but gradually began to be used to describe music played with even more volume and intensity. While hard rock maintained a bluesy rock and roll identity, including some swing in the back beat and riffs that tended to outline chord progressions in their hooks, heavy metal's riffs often functioned as stand-alone melodies and had no swing in them. Heavy metal took on "darker" characteristics after Black Sabbath's breakthrough at the beginning of the 1970s. In the 1980s it developed a number of subgenres, often termed extreme metal, some of which were influenced by hardcore punk, and which further differentiated the two styles. Despite this differentiation, hard rock and heavy metal have existed side by side, with bands frequently standing on the boundary of, or crossing between, the genres. |
By the end of the decade a distinct genre of hard rock was emerging with bands like Led Zeppelin, who mixed the music of early rock bands with a more hard-edged form of blues rock and acid rock on their first two albums Led Zeppelin (1969) and Led Zeppelin II (1969), and Deep Purple, who began as a progressive rock group but achieved their commercial breakthrough with their fourth and distinctively heavier album, In Rock (1970). Also significant was Black Sabbath's Paranoid (1970), which combined guitar riffs with dissonance and more explicit references to the occult and elements of Gothic horror. All three of these bands have been seen as pivotal in the development of heavy metal, but where metal further accentuated the intensity of the music, with bands like Judas Priest following Sabbath's lead into territory that was often "darker and more menacing", hard rock tended to continue to remain the more exuberant, good-time music. |
With the rise of disco in the US and punk rock in the UK, hard rock's mainstream dominance was rivalled toward the later part of the decade. Disco appealed to a more diverse group of people and punk seemed to take over the rebellious role that hard rock once held. Early punk bands like The Ramones explicitly rebelled against the drum solos and extended guitar solos that characterised stadium rock, with almost all of their songs clocking in around two minutes with no guitar solos. However, new rock acts continued to emerge and record sales remained high into the 1980s. 1977 saw the début and rise to stardom of Foreigner, who went on to release several platinum albums through to the mid-1980s. Midwestern groups like Kansas, REO Speedwagon and Styx helped further cement heavy rock in the Midwest as a form of stadium rock. In 1978, Van Halen emerged from the Los Angeles music scene with a sound based around the skills of lead guitarist Eddie Van Halen. He popularised a guitar-playing technique of two-handed hammer-ons and pull-offs called tapping, showcased on the song "Eruption" from the album Van Halen, which was highly influential in re-establishing hard rock as a popular genre after the punk and disco explosion, while also redefining and elevating the role of electric guitar. |
Established acts benefited from the new commercial climate, with Whitesnake's self-titled album (1987) selling over 17 million copies, outperforming anything in Coverdale's or Deep Purple's catalogue before or since. It featured the rock anthem "Here I Go Again '87" as one of 4 UK top 20 singles. The follow-up Slip of the Tongue (1989) went platinum, but according to critics Steve Erlwine and Greg Prato, "it was a considerable disappointment after the across-the-board success of Whitesnake". Aerosmith's comeback album Permanent Vacation (1987) would begin a decade long revival of their popularity. Crazy Nights (1987) by Kiss was the band's highest charting release in the US since 1979 and the highest of their career in the UK. Mötley Crüe with Girls, Girls, Girls (1987) continued their commercial success and Def Leppard with Hysteria (1987) hit their commercial peak, the latter producing seven hit singles (a record for a hard rock act). Guns N' Roses released the best-selling début of all time, Appetite for Destruction (1987). With a "grittier" and "rawer" sound than most glam metal, it produced three top 10 hits, including the number one "Sweet Child O' Mine". Some of the glam rock bands that formed in the mid-1980s, such as White Lion and Cinderella experienced their biggest success during this period with their respective albums Pride (1987) and Long Cold Winter (1988) both going multi-platinum and launching a series of hit singles. In the last years of the decade, the most notable successes were New Jersey (1988) by Bon Jovi, OU812 (1988) by Van Halen, Open Up and Say... Ahh! (1988) by Poison, Pump (1989) by Aerosmith, and Mötley Crüe's most commercially successful album Dr. Feelgood (1989). New Jersey spawned five Top 10 singles, a record for a hard rock act. In 1988 from 25 June to 5 November, the number one spot on the Billboard 200 album chart was held by a hard rock album for 18 out of 20 consecutive weeks; the albums were OU812, Hysteria, Appetite for Destruction, and New Jersey. A final wave of glam rock bands arrived in the late 1980s, and experienced success with multi-platinum albums and hit singles from 1989 until the early 1990s, among them Extreme, Warrant Slaughter and FireHouse. Skid Row also released their eponymous début (1989), reaching number six on the Billboard 200, but they were to be one of the last major bands that emerged in the glam rock era. |
A few hard rock bands from the 1970s and 1980s managed to sustain highly successful recording careers. Bon Jovi were still able to achieve a commercial hit with "It's My Life" from their double platinum-certified album Crush (2000). and AC/DC released the platinum-certified Stiff Upper Lip (2000) Aerosmith released a number two platinum album, Just Push Play (2001), which saw the band foray further into pop with the Top 10 hit "Jaded", and a blues cover album, Honkin' on Bobo, which reached number five in 2004. Heart achieved their first Top 10 album since the early 90s with Red Velvet Car in 2010, becoming the first female-led hard rock band to earn Top 10 albums spanning five decades. There were reunions and subsequent tours from Van Halen (with Hagar in 2004 and then Roth in 2007), The Who (delayed in 2002 by the death of bassist John Entwistle until 2006) and Black Sabbath (with Osbourne 1997–2006 and Dio 2006–2010) and even a one off performance by Led Zeppelin (2007), renewing the interest in previous eras. Additionally, hard rock supergroups, such as Audioslave (with former members of Rage Against the Machine and Soundgarden) and Velvet Revolver (with former members of Guns N' Roses, punk band Wasted Youth and Stone Temple Pilots singer Scott Weiland), emerged and experienced some success. However, these bands were short-lived, ending in 2007 and 2008, respectively. The long awaited Guns N' Roses album Chinese Democracy was finally released in 2008, but only went platinum and failed to come close to the success of the band's late 1980s and early 1990s material. More successfully, AC/DC released the double platinum-certified Black Ice (2008). Bon Jovi continued to enjoy success, branching into country music with "Who Says You Can't Go Home", which reached number one on the Hot Country Singles chart in 2006, and the rock/country album Lost Highway, which reached number one in 2007. In 2009, Bon Jovi released another number one album, The Circle, which marked a return to their hard rock sound. |
The term "Great Plains", for the region west of about the 96th or 98th meridian and east of the Rocky Mountains, was not generally used before the early 20th century. Nevin Fenneman's 1916 study, Physiographic Subdivision of the United States, brought the term Great Plains into more widespread usage. Before that the region was almost invariably called the High Plains, in contrast to the lower Prairie Plains of the Midwestern states. Today the term "High Plains" is used for a subregion of the Great Plains. |
Much of the Great Plains became open range, or rangeland where cattle roamed free, hosting ranching operations where anyone was theoretically free to run cattle. In the spring and fall, ranchers held roundups where their cowboys branded new calves, treated animals and sorted the cattle for sale. Such ranching began in Texas and gradually moved northward. In 1866-95, cowboys herded 10 million cattle north to rail heads such as Dodge City, Kansas and Ogallala, Nebraska; from there, cattle were shipped eastward. |
With the arrival of Francisco Vázquez de Coronado, a Spanish conquistador, the first recorded history of encounter between Europeans and Native Americans in the Great Plains occurred in Texas, Kansas and Nebraska from 1540-1542. In that same time period, Hernando de Soto crossed a west-northwest direction in what is now Oklahoma and Texas. Today this is known as the De Soto Trail. The Spanish thought the Great Plains were the location of the mythological Quivira and Cíbola, a place said to be rich in gold. |
The 100th meridian roughly corresponds with the line that divides the Great Plains into an area that receive 20 inches (510 millimetres) or more of rainfall per year and an area that receives less than 20 in (510 mm). In this context, the High Plains, as well as Southern Alberta, south-western Saskatchewan and Eastern Montana are mainly semi hot steppe land and are generally characterised by rangeland or marginal farmland. The region (especially the High Plains) is periodically subjected to extended periods of drought; high winds in the region may then generate devastating dust storms. The eastern Great Plains near the eastern boundary falls in the humid subtropical climate zone in the southern areas, and the northern and central areas fall in the humid continental climate. |
After 1870, the new railroads across the Plains brought hunters who killed off almost all the bison for their hides. The railroads offered attractive packages of land and transportation to European farmers, who rushed to settle the land. They (and Americans as well) also took advantage of the homestead laws to obtain free farms. Land speculators and local boosters identified many potential towns, and those reached by the railroad had a chance, while the others became ghost towns. In Kansas, for example, nearly 5000 towns were mapped out, but by 1970 only 617 were actually operating. In the mid-20th century, closeness to an interstate exchange determined whether a town would flourish or struggle for business. |
The rural Plains have lost a third of their population since 1920. Several hundred thousand square miles (several hundred thousand square kilometers) of the Great Plains have fewer than 6 inhabitants per square mile (2.3 inhabitants per square kilometer)—the density standard Frederick Jackson Turner used to declare the American frontier "closed" in 1893. Many have fewer than 2 inhabitants per square mile (0.77 inhabitants per square kilometer). There are more than 6,000 ghost towns in the state of Kansas alone, according to Kansas historian Daniel Fitzgerald. This problem is often exacerbated by the consolidation of farms and the difficulty of attracting modern industry to the region. In addition, the smaller school-age population has forced the consolidation of school districts and the closure of high schools in some communities. The continuing population loss has led some to suggest that the current use of the drier parts of the Great Plains is not sustainable, and there has been a proposal - the "Buffalo Commons" - to return approximately 139,000 square miles (360,000 km2) of these drier parts to native prairie land. |
Although the eastern image of farm life in the prairies emphasized the isolation of the lonely farmer and wife, plains residents created busy social lives for themselves. They often sponsored activities that combined work, food and entertainment such as barn raisings, corn huskings, quilting bees, Grange meetings, church activities and school functions. Women organized shared meals and potluck events, as well as extended visits between families. The Grange was a nationwide farmers' organization, they reserved high offices for women, and gave them a voice in public affairs. |
From the 1950s on, many areas of the Great Plains have become productive crop-growing areas because of extensive irrigation on large landholdings. The United States is a major exporter of agricultural products. The southern portion of the Great Plains lies over the Ogallala Aquifer, a huge underground layer of water-bearing strata dating from the last ice age. Center pivot irrigation is used extensively in drier sections of the Great Plains, resulting in aquifer depletion at a rate that is greater than the ground's ability to recharge. |
The Great Plains is the broad expanse of flat land (a plain), much of it covered in prairie, steppe and grassland, that lies west of the Mississippi River tallgrass prairie states and east of the Rocky Mountains in the United States and Canada. This area covers parts, but not all, of the states of Colorado, Kansas, Montana, Nebraska, New Mexico, North Dakota, Oklahoma, South Dakota, Texas, and Wyoming, and the Canadian provinces of Alberta, Manitoba and Saskatchewan. The region is known for supporting extensive cattle ranching and dry farming. |
The North American Environmental Atlas, produced by the Commission for Environmental Cooperation, a NAFTA agency composed of the geographical agencies of the Mexican, American, and Canadian governments uses the "Great Plains" as an ecoregion synonymous with predominant prairies and grasslands rather than as physiographic region defined by topography. The Great Plains ecoregion includes five sub-regions: Temperate Prairies, West-Central Semi-Arid Prairies, South-Central Semi-Arid Prairies, Texas Louisiana Coastal Plains, and Tamaulipus-Texas Semi-Arid Plain, which overlap or expand upon other Great Plains designations. |
The railroads opened up the Great Plains for settlement, for now it was possible to ship wheat and other crops at low cost to the urban markets in the East, and Europe. Homestead land was free for American settlers. Railroads sold their land at cheap rates to immigrants in expectation they would generate traffic as soon as farms were established. Immigrants poured in, especially from Germany and Scandinavia. On the plains, very few single men attempted to operate a farm or ranch by themselves; they clearly understood the need for a hard-working wife, and numerous children, to handle the many chores, including child-rearing, feeding and clothing the family, managing the housework, feeding the hired hands, and, especially after the 1930s, handling paperwork and financial details. During the early years of settlement, farm women played an integral role in assuring family survival by working outdoors. After approximately one generation, women increasingly left the fields, thus redefining their roles within the family. New technology including sewing and washing machines encouraged women to turn to domestic roles. The scientific housekeeping movement, promoted across the land by the media and government extension agents, as well as county fairs which featured achievements in home cookery and canning, advice columns for women regarding farm bookkeeping, and home economics courses in the schools. |
During the Cenozoic era, specifically about 25 million years ago during the Miocene and Pliocene epochs, the continental climate became favorable to the evolution of grasslands. Existing forest biomes declined and grasslands became much more widespread. The grasslands provided a new niche for mammals, including many ungulates and glires, that switched from browsing diets to grazing diets. Traditionally, the spread of grasslands and the development of grazers have been strongly linked. However, an examination of mammalian teeth suggests that it is the open, gritty habitat and not the grass itself which is linked to diet changes in mammals, giving rise to the "grit, not grass" hypothesis. |
To allow for agricultural development of the Great Plains and house a growing population, the US passed the Homestead Acts of 1862: it allowed a settler to claim up to 160 acres (65 ha) of land, provided that he lived on it for a period of five years and cultivated it. The provisions were expanded under the Kinkaid Act of 1904 to include a homestead of an entire section. Hundreds of thousands of people claimed such homesteads, sometimes building sod houses out of the very turf of their land. Many of them were not skilled dryland farmers and failures were frequent. Much of the Plains were settled during relatively wet years. Government experts did not understand how farmers should cultivate the prairies and gave advice counter to what would have worked[citation needed]. Germans from Russia who had previously farmed, under similar circumstances, in what is now Ukraine were marginally more successful than other homesteaders. The Dominion Lands Act of 1871 served a similar function for establishing homesteads on the prairies in Canada. |
Infrared radiation is used in industrial, scientific, and medical applications. Night-vision devices using active near-infrared illumination allow people or animals to be observed without the observer being detected. Infrared astronomy uses sensor-equipped telescopes to penetrate dusty regions of space, such as molecular clouds; detect objects such as planets, and to view highly red-shifted objects from the early days of the universe. Infrared thermal-imaging cameras are used to detect heat loss in insulated systems, to observe changing blood flow in the skin, and to detect overheating of electrical apparatus. |
The onset of infrared is defined (according to different standards) at various values typically between 700 nm and 800 nm, but the boundary between visible and infrared light is not precisely defined. The human eye is markedly less sensitive to light above 700 nm wavelength, so longer wavelengths make insignificant contributions to scenes illuminated by common light sources. However, particularly intense near-IR light (e.g., from IR lasers, IR LED sources, or from bright daylight with the visible light removed by colored gels) can be detected up to approximately 780 nm, and will be perceived as red light. Sources providing wavelengths as long as 1050 nm can be seen as a dull red glow in intense sources, causing some difficulty in near-IR illumination of scenes in the dark (usually this practical problem is solved by indirect illumination). Leaves are particularly bright in the near IR, and if all visible light leaks from around an IR-filter are blocked, and the eye is given a moment to adjust to the extremely dim image coming through a visually opaque IR-passing photographic filter, it is possible to see the Wood effect that consists of IR-glowing foliage. |
The concept of emissivity is important in understanding the infrared emissions of objects. This is a property of a surface that describes how its thermal emissions deviate from the ideal of a black body. To further explain, two objects at the same physical temperature will not show the same infrared image if they have differing emissivity. For example, for any pre-set emissivity value, objects with higher emissivity will appear hotter, and those with a lower emissivity will appear cooler. For that reason, incorrect selection of emissivity will give inaccurate results when using infrared cameras and pyrometers. |
Infrared vibrational spectroscopy (see also near-infrared spectroscopy) is a technique that can be used to identify molecules by analysis of their constituent bonds. Each chemical bond in a molecule vibrates at a frequency characteristic of that bond. A group of atoms in a molecule (e.g., CH2) may have multiple modes of oscillation caused by the stretching and bending motions of the group as a whole. If an oscillation leads to a change in dipole in the molecule then it will absorb a photon that has the same frequency. The vibrational frequencies of most molecules correspond to the frequencies of infrared light. Typically, the technique is used to study organic compounds using light radiation from 4000–400 cm−1, the mid-infrared. A spectrum of all the frequencies of absorption in a sample is recorded. This can be used to gain information about the sample composition in terms of chemical groups present and also its purity (for example, a wet sample will show a broad O-H absorption around 3200 cm−1). |
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