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After a big dip of sales in 2012, consumer digital camera sales declined again in 2013 by 36 percent. In 2011, compact digital cameras sold 10 million per month. In 2013, sales fell to about 4 million per month. DSLR and MILC sales also declined in 2013 by 10–15% after almost ten years of double digit growth.
Worldwide unit sales of digital cameras is continuously declining from 148 million in 2011 to 58 million in 2015 and tends to decrease more in the following years.
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Film camera sales hit their peak at about 37 million units in 1997, while digital camera sales began in 1989. By 2008, the film camera market had died and digital camera sales hit their peak at 121 million units in 2010. In 2002, cell phones with an integrated camera had been introduced and in 2003 the cell phone with an integrated camera had sold 80 million units per year. By 2011, cell phones with an integrated camera were selling hundreds of millions per year, which were causing a decline in digital cameras. In 2015, digital camera sales were 35 million units or only less than a third of digital camera sales numbers at their peak and also slightly less than film camera sold number at their peak.
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Many digital cameras can connect directly to a computer to transfer data:-
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A common alternative is the use of a card reader which may be capable of reading several types of storage media, as well as high speed transfer of data to the computer. Use of a card reader also avoids draining the camera battery during the download process. An external card reader allows convenient direct access to the images on a collection of storage media. But if only one storage card is in use, moving it back and forth between the camera and the reader can be inconvenient. Many computers have a card reader built in, at least for SD cards.
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Many modern cameras support the PictBridge standard, which allows them to send data directly to a PictBridge-capable printer without the need for a computer. PictBridge uses PTP to transfer images and control information.
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Wireless connectivity can also provide for printing photos without a cable connection.
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An instant-print camera, is a digital camera with a built-in printer. This confers a similar functionality as an instant camera which uses instant film to quickly generate a physical photograph. Such non-digital cameras were popularized by Polaroid with the SX-70 in 1972.
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Many digital cameras include a video output port. Usually sVideo, it sends a standard-definition video signal to a television, allowing the user to show one picture at a time. Buttons or menus on the camera allow the user to select the photo, advance from one to another, or automatically send a "slide show" to the TV.
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HDMI has been adopted by many high-end digital camera makers, to show photos in their high-resolution quality on an HDTV.
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In January 2008, Silicon Image announced a new technology for sending video from mobile devices to a television in digital form. MHL sends pictures as a video stream, up to 1080p resolution, and is compatible with HDMI.
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Some DVD recorders and television sets can read memory cards used in cameras; alternatively several types of flash card readers have TV output capability.
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Cameras can be equipped with a varying amount of environmental sealing to provide protection against splashing water, moisture , dust and sand, or complete waterproofness to a certain depth and for a certain duration. The latter is one of the approaches to allow underwater photography, the other approach being the use of waterproof housings. Many waterproof digital cameras are also shockproof and resistant to low temperatures.
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Some waterproof cameras can be fitted with a waterproof housing to increase the operational depth range. The Olympus 'Tough' range of compact cameras is an example.
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Many digital cameras have preset modes for different applications. Within the constraints of correct exposure various parameters can be changed, including exposure, aperture, focusing, light metering, white balance, and equivalent sensitivity. For example, a portrait might use a wider aperture to render the background out of focus, and would seek out and focus on a human face rather than other image content.
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Few cameras are equipped with a voice note recording feature.
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Vendors implement a variety scene modes in cameras' firmwares for various purposes, such as a "landscape mode" which prevents focusing on rainy and/or stained window glass such as a windshield, and a "sports mode" which reduces motion blur of moving subjects by reducing exposure time with the help of increased light sensitivity. Firmwares may be equipped with the ability to select a suitable scene mode automatically through artificial intelligence.
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Many camera phones and most stand alone digital cameras store image data in flash memory cards or other removable media. Most stand-alone cameras use SD format, while a few use CompactFlash or other types. In January 2012, a faster XQD card format was announced. In early 2014, some high end cameras have two hot-swappable memory slots. Photographers can swap one of the memory card with camera-on. Each memory slot can accept either Compact Flash or SD Card. All new Sony cameras also have two memory slots, one for its Memory Stick and one for SD Card, but not hot-swapable.
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The approximate count of remaining photos until space exhaustion is calculated by the firmware throughout use and indicated in the viewfinder, to prepare the user for an impending necessary hot swap of the memory card, and/or file offload.
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A few cameras used other removable storage such as Microdrives , CD single , and 3.5" floppy disks . Other unusual formats include:
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Most manufacturers of digital cameras do not provide drivers and software to allow their cameras to work with Linux or other free software. Still, many cameras use the standard USB mass storage and/or Media Transfer Protocol, and are thus widely supported. Other cameras are supported by the gPhoto project, and many computers are equipped with a memory card reader.
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The Joint Photography Experts Group standard is the most common file format for storing image data. Other file types include Tagged Image File Format and various Raw image formats.
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Many cameras, especially high-end ones, support a raw image format. A raw image is the unprocessed set of pixel data directly from the camera's sensor, often saved in a proprietary format. Adobe Systems has released the DNG format, a royalty-free raw image format used by at least 10 camera manufacturers.
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Raw files initially had to be processed in specialized image editing programs, but over time many mainstream editing programs, such as Google's Picasa, have added support for raw images. Rendering to standard images from raw sensor data allows more flexibility in making major adjustments without losing image quality or retaking the picture.
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Formats for movies are AVI, DV, MPEG, MOV , WMV, and ASF . Recent formats include MP4, which is based on the QuickTime format and uses newer compression algorithms to allow longer recording times in the same space.
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Other formats that are used in cameras are the Design Rule for Camera Format , an ISO specification, used in almost all camera since 1998, which defines an internal file structure and naming. Also used is the Digital Print Order Format , which dictates what order images are to be printed in and how many copies. The DCF 1998 defines a logical file system with 8.3 filenames and makes the usage of either FAT12, FAT16, FAT32 or exFAT mandatory for its physical layer in order to maximize platform interoperability.
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Most cameras include Exif data that provides metadata about the picture. Exif data may include aperture, exposure time, focal length, date and time taken. Some are able to tag the location.
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In order to guarantee interoperability, DCF specifies the file system for image and sound files to be used on formatted DCF media as FAT12, FAT16, FAT32, or exFAT. Media with a capacity of more than 2 GB must be formatted using FAT32 or exFAT.
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The filesystem in a digital camera contains a DCIM directory, which can contain multiple subdirectories with names such as "123ABCDE" that consist of a unique directory number and five alphanumeric characters, which may be freely chosen and often refer to a camera maker. These directories contain files with names such as "ABCD1234.JPG" that consist of four alphanumeric characters , followed by a number. Handling of directories with possibly user-created duplicate numbers may vary among camera firmwares.
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DCF 2.0 adds support for DCF optional files recorded in an optional color space . Such files must be indicated by a leading "_" .
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To enable loading many images in miniature view quickly and efficiently, and to retain meta data, some vendors' firmwares generate accompanying low-resolution thumbnail files for videos and raw photos. For example, those of Canon cameras end with .THM. JPEG can already store a thumbnail image standalone.
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Digital cameras have become smaller over time, resulting in an ongoing need to develop a battery small enough to fit in the camera and yet able to power it for a reasonable length of time.
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Digital cameras utilize either proprietary or standard consumer batteries. As of March 2014, most cameras use proprietary lithium-ion batteries while some use standard AA batteries or primarily use a proprietary Lithium-ion rechargeable battery pack but have an optional AA battery holder available.
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The most common class of battery used in digital cameras is proprietary battery formats. These are built to a manufacturer's custom specifications. Almost all proprietary batteries are lithium-ion. In addition to being available from the OEM, aftermarket replacement batteries are commonly available for most camera models.
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Digital cameras that utilize off-the-shelf batteries are typically designed to be able to use both single-use disposable and rechargeable batteries, but not with both types in use at the same time. The most common off-the-shelf battery size used is AA. CR2, CR-V3 batteries, and AAA batteries are also used in some cameras. The CR2 and CR-V3 batteries are lithium based, intended for a single use. Rechargeable RCR-V3 lithium-ion batteries are also available as an alternative to non-rechargeable CR-V3 batteries.
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Some battery grips for DSLRs come with a separate holder to accommodate AA cells as an external power source.
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When digital cameras became common, many photographers asked whether their film cameras could be converted to digital. The answer was not immediately clear, as it differed among models. For the majority of 35 mm film cameras the answer is no, the reworking and cost would be too great, especially as lenses have been evolving as well as cameras. For most a conversion to digital, to give enough space for the electronics and allow a liquid crystal display to preview, would require removing the back of the camera and replacing it with a custom built digital unit.
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Many early professional SLR cameras, such as the Kodak DCS series, were developed from 35 mm film cameras. The technology of the time, however, meant that rather than being digital "backs" the bodies of these cameras were mounted on large, bulky digital units, often bigger than the camera portion itself. These were factory built cameras, however, not aftermarket conversions.
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A notable exception is the Nikon E2 and Nikon E3, using additional optics to convert the 35 mm format to a 2/3 CCD-sensor.
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A few 35 mm cameras have had digital camera backs made by their manufacturer, Leica being a notable example. Medium format and large format cameras , have a low unit production, and typical digital backs for them cost over $10,000. These cameras also tend to be highly modular, with handgrips, film backs, winders, and lenses available separately to fit various needs.
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The very large sensor these backs use leads to enormous image sizes. For example, Phase One's P45 39 MP image back creates a single TIFF image of size up to 224.6 MB, and even greater pixel counts are available. Medium format digitals such as this are geared more towards studio and portrait photography than their smaller DSLR counterparts; the ISO speed in particular tends to have a maximum of 400, versus 6400 for some DSLR cameras. .
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In the industrial and high-end professional photography market, some camera systems use modular image sensors. For example, some medium format SLR cameras, such as the Mamiya 645D series, allow installation of either a digital camera back or a traditional photographic film back.
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Linear array cameras are also called scan backs.
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Most earlier digital camera backs used linear array sensors, moving vertically to digitize the image. Many of them only capture grayscale images. The relatively long exposure times, in the range of seconds or even minutes generally limit scan backs to studio applications, where all aspects of the photographic scene are under the photographer's control.
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Some other camera backs use CCD arrays similar to typical cameras. These are called single-shot backs.
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Since it is much easier to manufacture a high-quality linear CCD array with only thousands of pixels than a CCD matrix with millions, very high resolution linear CCD camera backs were available much earlier than their CCD matrix counterparts. For example, you could buy an camera back with over 7,000 pixel horizontal resolution in the mid-1990s. However, as of 2004, it is still difficult to buy a comparable CCD matrix camera of the same resolution. Rotating line cameras, with about 10,000 color pixels in its sensor line, are able, as of 2005, to capture about 120,000 lines during one full 360 degree rotation, thereby creating a single digital image of 1,200 Megapixels.
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Most modern digital camera backs use CCD or CMOS matrix sensors. The matrix sensor captures the entire image frame at once, instead of incrementing scanning the frame area through the prolonged exposure. For example, Phase One produces a 39 million pixel digital camera back with a 49.1 x 36.8 mm CCD in 2008. This CCD array is a little smaller than a frame of 120 film and much larger than a 35 mm frame . In comparison, consumer digital cameras use arrays ranging from 36 x 24 mm to 1.28 x 0.96 mm CMOS sensor.
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A computer keyboard is a peripheral input device modeled after the typewriter keyboard which uses an arrangement of buttons or keys to act as mechanical levers or electronic switches. Replacing early punched cards and paper tape technology, interaction via teleprinter-style keyboards have been the main input method for computers since the 1970s, supplemented by the computer mouse since the 1980s.
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Keyboard keys typically have a set of characters engraved or printed on them, and each press of a key typically corresponds to a single written symbol. However, producing some symbols may require pressing and holding several keys simultaneously or in sequence.
While most keys produce characters , other keys can prompt the computer to execute system commands. In a modern computer, the interpretation of key presses is generally left to the software: the information sent to the computer, the scan code, tells it only which physical key was pressed or released.
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In normal usage, the keyboard is used as a text entry interface for typing text, numbers, and symbols into application software such as a word processor, web browser or social media app.
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Touchscreens use virtual keyboards.
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Typewriters are the definitive ancestor of all key-based text entry devices, but the computer keyboard as a device for electromechanical data entry and communication largely comes from the utility of two devices: teleprinters and keypunches. It was through such devices that modern computer keyboards inherited their layouts.
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As early as the 1870s, teleprinter-like devices were used to simultaneously type and transmit stock market text data from the keyboard across telegraph lines to stock ticker machines to be immediately copied and displayed onto ticker tape. The teleprinter, in its more contemporary form, was developed from 1907 to 1910 by American mechanical engineer Charles Krum and his son Howard, with early contributions by electrical engineer Frank Pearne. Earlier models were developed separately by individuals such as Royal Earl House and Frederick G. Creed.
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Earlier, Herman Hollerith developed the first keypunch devices, which soon evolved to include keys for text and number entry akin to normal typewriters by the 1930s.
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The keyboard on the teleprinter played a strong role in point-to-point and point-to-multipoint communication for most of the 20th century, while the keyboard on the keypunch device played a strong role in data entry and storage for just as long. The development of some of the earliest computers incorporated electric typewriter keyboards: the development of the ENIAC computer incorporated a keypunch device as both the input and paper-based output device, and the BINAC computer made use of an electromechanically controlled typewriter for both data entry onto magnetic tape and data output.
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The keyboard remained the primary, most integrated computer peripheral well into the era of personal computing until the introduction of the mouse as a consumer device in 1984. By this time, text-only user interfaces with sparse graphics gave way to comparatively graphics-rich icons on screen. However, keyboards remain central to human-computer interaction to the present though mobile personal computing devices such as smartphones and tablets use a virtual keyboard.
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Different types of keyboards are available and each is designed with a focus on specific features that suit particular needs. Today, most full-size keyboards use one of three different mechanical layouts, usually referred to as simply ISO , ANSI , and JIS , referring roughly to the organizations issuing the relevant worldwide, United States, and Japanese standards, respectively. ANSI standard alphanumeric keyboards have keys that are on three-quarter inch centers ), and have a key travel of at least 0.15 inches .
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Modern keyboard models contain a set number of total keys according to their given standard, described as 101, 104, 105, etc. and sold as "Full-size" keyboards. Modern keyboards matching US conventions typically have 104 keys while the 105 key layout is the norm in the rest of the world. This number is not always followed, and individual keys or whole sections are commonly skipped for the sake of compactness or user preference. The most common choice is to not include the numpad, which can usually be fully replaced by the alphanumeric section; such designs are referred to as "tenkeyless". Laptops and wireless peripherals often lack duplicate keys and ones seldom used. Function- and arrow keys are nearly always present.
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Another factor determining the size of a keyboard is the size and spacing of the keys. The reduction is limited by the practical consideration that the keys must be large enough to be easily pressed by fingers. Alternatively, a tool is used for pressing small keys.
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Desktop computer keyboards include alphabetic characters and numerals , typographical symbols and punctuation marks, one or more currency symbols and other special characters, diacritics and a variety of function keys. The repertoire of glyphs engraved on the keys of a keyboard accords with national conventions and language needs. Computer keyboards are similar to electric-typewriter keyboards but contain additional keys, such as the command key or Windows keys.
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Keyboards on laptops and notebook computers usually have a shorter travel distance for the keystroke, shorter over travel distance, and a reduced set of keys. They may not have a numeric keypad, and the function keys may be placed in locations that differ from their placement on a standard, full-sized keyboard. The switch mechanism for a laptop keyboard is more likely to be a scissor switch than a rubber dome; this is opposite the trend for full-size keyboards.
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Flexible keyboards are a junction between normal type and laptop type keyboards: normal from the full arrangement of keys, and laptop from the short key distance. Additionally, the flexibility allows the user to fold/roll the keyboard for better storage and transfer. However, for typing the keyboard must be resting on a hard surface. The vast majority of flexible keyboards in the market are made from silicone; this material makes them water- and dust-proof. This is useful in hospitals, where keyboards are subjected to frequent washing,
and other dirty or must-be-clean environments.
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Handheld ergonomic keyboards are designed to be held like a game controller, and can be used as such, instead of laid out flat on top of a table surface.
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Typically handheld keyboards hold all the alphanumeric keys and symbols that a standard keyboard would have, yet only be accessed by pressing two sets of keys at once; one acting as a function key similar to a 'Shift' key that would allow for capital letters on a standard keyboard. Handheld keyboards allow the user the ability to move around a room or to lean back on a chair while also being able to type in front or away from the computer. Some variations of handheld ergonomic keyboards also include a trackball mouse that allow mouse movement and typing included in one handheld device.
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Smaller external keyboards have been introduced for devices without a built-in keyboard, such as PDAs, and smartphones. Small keyboards are also useful where there is a limited workspace.
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A thumb keyboard is used in some personal digital assistants such as the Palm Treo and BlackBerry and some Ultra-Mobile PCs such as the OQO.
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Numeric keyboards contain only numbers, mathematical symbols for addition, subtraction, multiplication, and division, a decimal point, and several function keys. They are often used to facilitate data entry with smaller keyboards that do not have a numeric keypad, commonly those of laptop computers. These keys are collectively known as a numeric pad, numeric keys, or a numeric keypad, and it can consist of the following types of keys: Arithmetic operators, numbers, arrow keys, Navigation keys, Num Lock and Enter key.
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Multifunctional keyboards provide additional function beyond the standard keyboard. Many are programmable, configurable computer keyboards and some control multiple PCs, workstations and other information sources, usually in multi-screen work environments. Users have additional key functions as well as the standard functions and can typically use a single keyboard and mouse to access multiple sources.
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Multifunctional keyboards may feature customised keypads, fully programmable function or soft keys for macros/pre-sets, biometric or smart card readers, trackballs, etc. New generation multifunctional keyboards feature a touchscreen display to stream video, control audio visual media and alarms, execute application inputs, configure individual desktop environments, etc. Multifunctional keyboards may also permit users to share access to PCs and other information sources. Multiple interfaces are used to integrate external devices. Some multifunctional keyboards are also used to directly and intuitively control video walls.
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Common environments for multifunctional keyboards are complex, high-performance workplaces for financial traders and control room operators .
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Many keyboards have been designed for one-handed operation.
The first one, a chorded keyboard, was invented by Douglas Engelbart.
Other types of one-handed keyboards include the FrogPad, the Half-keyboard,
and one-handed Dvorak keyboard layouts designed for one hand typing.
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While other keyboards generally associate one action with each key, chorded keyboards associate actions with combinations of key presses. Since there are many combinations available, chorded keyboards can effectively produce more actions on a board with fewer keys. Court reporters' stenotype machines use chorded keyboards to enable them to enter text much faster by typing a syllable with each stroke instead of one letter at a time. The fastest typists use a stenograph, a kind of chorded keyboard used by most court reporters and closed-caption reporters. Some chorded keyboards are also made for use in situations where fewer keys are preferable, such as on devices that can be used with only one hand, and on small mobile devices that don't have room for larger keyboards. Chorded keyboards are less desirable in many cases because it usually takes practice and memorization of the combinations to become proficient.
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Virtual keyboards, sometimes called on-screen keyboards , consist of computer programs that display an image of a keyboard on the screen. Another input device such as a mouse or a touchscreen can be used to operate each virtual key to enter text. Virtual keyboards have become very popular in touchscreen enabled cell phones due to the additional cost and space requirements of other types of hardware keyboards. Microsoft Windows, Mac OS X, and some varieties of Linux include on-screen keyboards that can be controlled with the mouse. In these, the mouse has to be maneuvered onto the on-screen letters given by the software. On the click of a letter, the software writes the respective letter in the respective spot.
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Projection keyboards project an image of keys, usually with a laser, onto a flat surface. The device then uses a camera or infrared sensor to "watch" where the user's fingers move, and will count a key as being pressed when it "sees" the user's finger touch the projected image. Projection keyboards can simulate a full size keyboard from a very small projector. Because the "keys" are simply projected images, they cannot be felt when pressed. Users of projected keyboards often experience increased discomfort in their fingertips because of the lack of "give" when typing. A flat, non-reflective surface is also required for the keys to be projected. Most projection keyboards are made for use with PDAs and smartphones due to their small form factor.
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Also known as photo-optical keyboard, light responsive keyboard, photo-electric keyboard and optical key actuation detection technology.
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An optical keyboard technology utilizes LEDs and photo sensors to optically detect actuated keys. Most commonly the emitters and sensors are located in the perimeter, mounted on a small PCB. The light is directed from side to side of the keyboard interior and it can only be blocked by the actuated keys. Most optical keyboards require at least 2 beams to determine the actuated key. Some optical keyboards use a special key structure that blocks the light in a certain pattern, allowing only one beam per row of keys .
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Alphabetical, numeric, and punctuation keys are used in the same fashion as a typewriter keyboard to enter their respective symbol into a word processing program, text editor, data spreadsheet, or other program. Many of these keys will produce different symbols when modifier keys or shift keys are pressed. The alphabetic characters become uppercase when the shift key or Caps Lock key is depressed. The numeric characters become symbols or punctuation marks when the shift key is depressed. The alphabetical, numeric, and punctuation keys can also have other functions when they are pressed at the same time as some modifier keys.
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The Space bar is a horizontal bar in the lowermost row, which is significantly wider than other keys. Like the alphanumeric characters, it is also descended from the mechanical typewriter. Its main purpose is to enter the space between words during typing. It is large enough so that a thumb from either hand can use it easily. Depending on the operating system, when the space bar is used with a modifier key such as the control key, it may have functions such as resizing or closing the current window, half-spacing, or backspacing. In computer games and other applications the key has myriad uses in addition to its normal purpose in typing, such as jumping and adding marks to check boxes. In certain programs for playback of digital video, the space bar is used for pausing and resuming the playback.
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Modifier keys are special keys that modify the normal action of another key, when the two are pressed in combination. For example, Alt+F4 in Microsoft Windows will close the program in an active window. In contrast, pressing just F4 will probably do nothing, unless assigned a specific function in a particular program. By themselves, modifier keys usually do nothing.
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The most widely used modifier keys include the Control key, Shift key and the Alt key. The AltGr key is used to access additional symbols for keys that have three symbols printed on them. On the Macintosh and Apple keyboards, the modifier keys are the Option key and Command key, respectively. On Sun Microsystems and Lisp machine keyboards, the Meta key is used as a modifier and for Windows keyboards, there is a Windows key. Compact keyboard layouts often use a Fn key. "Dead keys" allow placement of a diacritic mark, such as an accent, on the following letter .
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The enter/return key typically causes a command line, window form or dialog box to operate its default function, which is typically to finish an "entry" and begin the desired process. In word processing applications, pressing the enter key ends a paragraph and starts a new one.
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Navigation keys or cursor keys include a variety of keys which move the cursor to different positions on the screen. Arrow keys are programmed to move the cursor in a specified direction; page scroll keys, such as the Page Up and Page Down keys, scroll the page up and down. The Home key is used to return the cursor to the beginning of the line where the cursor is located; the End key puts the cursor at the end of the line. The Tab key advances the cursor to the next tab stop.
The Insert key is mainly used to switch between overtype mode, in which the cursor overwrites any text that is present on and after its current location, and insert mode, where the cursor inserts a character at its current position, forcing all characters past it one position further. The Delete key discards the character ahead of the cursor's position, moving all following characters one position "back" towards the freed place. On many notebook computer keyboards the key labeled Delete serves the same purpose as a Backspace key. The Backspace key deletes the preceding character.
Lock keys lock part of a keyboard, depending on the settings selected. The lock keys are scattered around the keyboard. Most styles of keyboards have three LEDs indicating which locks are enabled, in the upper right corner above the numeric pad. The lock keys include Scroll lock, Num lock , and Caps lock.
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The SysRq and Print screen commands often share the same key. SysRq was used in earlier computers as a "panic" button to recover from crashes . The Print screen command used to capture the entire screen and send it to the printer, but in the present it usually puts a screenshot in the clipboard.
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The Break key/Pause key no longer has a well-defined purpose. Its origins go back to teleprinter users, who wanted a key that would temporarily interrupt the communications line. The Break key can be used by software in several different ways, such as to switch between multiple login sessions, to terminate a program, or to interrupt a modem connection.
In programming, especially old DOS-style BASIC, Pascal and C, Break is used to stop program execution. In addition to this, Linux and variants, as well as many DOS programs, treat this combination the same as Ctrl+C. On modern keyboards, the break key is usually labeled Pause/Break. In most Windows environments, the key combination Windows key+Pause brings up the system properties.
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The escape key has a variety of meanings according to Operating System, application or both. "Nearly all of the time", it signals Stop, QUIT, or "let me get out of a dialog" . It triggers the Stop function in many web browsers.
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The escape key was part of the standard keyboard of the Teletype Model 33 . The DEC VT50, introduced July 1974, also had an Esc key. The TECO text editor and its descendant Emacs use the Esc key extensively.
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Historically it also served as a type of shift key, such that one or more following characters were interpreted differently, hence the term escape sequence, which refers to a series of characters, usually preceded by the escape character.
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On machines running Microsoft Windows, prior to the implementation of the Windows key on keyboards, the typical practice for invoking the "start" button was to hold down the control key and press escape. This process still works in Windows 95, 98, Me, NT 4, 2000, XP, Vista, 7, 8, and 10.
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The 'enter key' ⌅ Enter and 'return key' ↵ Return are two closely related keys with overlapping and distinct functions dependent on operating system and application. On full-size keyboards, there are two such keys, one in the alphanumeric keys and the other one is in the numeric keys. The purpose of the enter key is to confirm what has been typed. The return key is based on the original line feed/carriage return function of typewriters: in many word processors, for example, the return key ends a paragraph; in a spreadsheet, it completes the current cell and move to the next cell.
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The shape of the Enter key differs between ISO and ANSI keyboards: in the latter, the Enter key is in a single row while in the former it spans over two rows and has an inverse L shape.
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The purpose of the ⇧ Shift key is to invoke the first alternative function of the key with which it is pressed concurrently. For alphabetic keys, shift+letter gives the upper case version of that letter. For other keys, the key is engraved with symbols for both the unshifted and shifted result. When used in combination with other control keys , the effect is system and application dependent.
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The Menu key or Application key is a key found on Windows-oriented computer keyboards. It is used to launch a context menu with the keyboard rather than with the usual right mouse button. The key's symbol is usually a small icon depicting a cursor hovering above a menu. On some Samsung keyboards the cursor in the icon is not present, showing the menu only. This key was created at the same time as the Windows key. This key is normally used when the right mouse button is not present on the mouse. Some Windows public terminals do not have a Menu key on their keyboard to prevent users from right-clicking .
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Many, but not all, computer keyboards have a numeric keypad to the right of the alphabetic keyboard, often separated from the other groups of keys such as the function keys and system command keys, which contains numbers, basic mathematical symbols , and a few function keys. In addition to the row of number keys above the top alphabetic row, most desktop keyboards have a number pad or accounting pad, on the right hand side of the keyboard. While num lock is set, the numbers on these keys duplicate the number row; if not, they have alternative functions as engraved. In addition to numbers, this pad has command symbols concerned with calculations such as addition, subtraction, multiplication and division symbols. The enter key in this keys indicate the equal sign.
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On Japanese/Korean keyboards, there may be Language input keys for changing the language to use.
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5,694
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Some keyboards have power management keys ; Internet keys to access a web browser or E-mail; and/or multimedia keys, such as volume controls; or keys that can be programmed by the user to launch a specified application or a command like minimizing all windows.
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5,695
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It is possible to install multiple keyboard layouts within an operating system and switch between them, either through features implemented within the OS, or through an external application. Microsoft Windows, Linux, and Mac provide support to add keyboard layouts and choose from them.
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5,696
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Keyboards and keypads may be illuminated from inside, especially on equipment for mobile use. Both keyboards built into computers and external ones may support backlighting; external backlit keyboards may have a wired USB connection, or be connected wirelessly and powered by batteries. Illumination facilitates the use of the keyboard or keypad in dark environments.
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For general productivity, only the keys may be uniformly backlit, without distracting light around the keys.
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5,698
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Many gaming keyboards are designed to have an aesthetic as well as functional appeal, with multiple colours, and colour-coded keys to make it easier for gamers to find command keys while playing in a dark room. Many keyboards not otherwise illuminated may have small LED indicator lights in a few important function keys, or elsewhere on the housing, if their function is activated .
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5,699
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In the first electronic keyboards in the early 1970s, the key switches were individual switches inserted into holes in metal frames. These keyboards cost from 80 to 120 USD and were used in mainframe data terminals. The most popular switch types were reed switches .
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5,700
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In the mid-1970s, lower-cost direct-contact key switches were introduced, but their life in switch cycles was much shorter because they were open to the environment. This became more acceptable, however, for use in computer terminals at the time, which began to see increasingly shorter model lifespans as they advanced.
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