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4,100 | In 2017, there were more than 4,400 scientists undertaking research in Antarctica, a number that fell to just over 1,100 in the winter. There are over 70 permanent and seasonal research stations on the continent; the largest, United States McMurdo Station, is capable of housing more than 1,000 people. The British Antar... | https://en.wikipedia.org/wiki?curid=18959138 |
4,101 | Geologists primarily study plate tectonics, meteorites, and the breakup of Gondwana. Glaciologists study the history and dynamics of floating ice, seasonal snow, glaciers, and ice sheets. Biologists, in addition to researching wildlife, are interested in how low temperatures and the presence of humans affect adaptation... | https://en.wikipedia.org/wiki?curid=18959138 |
4,102 | The high elevation of the interior, the low temperatures, and the length of polar nights during the winter months all allow for better astronomical observations at Antarctica than anywhere else on Earth. The view of space from Earth is improved by a thinner atmosphere at higher elevations and a lack of water vapour in ... | https://en.wikipedia.org/wiki?curid=18959138 |
4,103 | Antarctica provides a unique environment for the study of meteorites: the dry polar desert preserves them well, and meteorites older than a million years have been found. They are relatively easy to find, as the dark stone meteorites stand out in a landscape of ice and snow, and the flow of ice accumulates them in cert... | https://en.wikipedia.org/wiki?curid=18959138 |
4,104 | Morse code is a method used in telecommunication to encode text characters as standardized sequences of two different signal durations, called "dots" and "dashes", or "dits" and "dahs". Morse code is named after Samuel Morse, one of the inventors of the telegraph. | https://en.wikipedia.org/wiki?curid=18935 |
4,105 | International Morse code encodes the 26 basic Latin letters ' through ', one accented Latin letter (), the Arabic numerals, and a small set of punctuation and procedural signals (prosigns). There is no distinction between upper and lower case letters. Each Morse code symbol is formed by a sequence of "dits" and "dahs".... | https://en.wikipedia.org/wiki?curid=18935 |
4,106 | Morse code can be memorized and sent in a form perceptible to the human senses, e.g. via sound waves or visible light, such that it can be directly interpreted by persons trained in the skill. Morse code is usually transmitted by on-off keying of an information-carrying medium such as electric current, radio waves, vis... | https://en.wikipedia.org/wiki?curid=18935 |
4,107 | Since many natural languages use more than the 26 letters of the Latin alphabet, Morse alphabets have been developed for those languages, largely by transliteration of existing codes. | https://en.wikipedia.org/wiki?curid=18935 |
4,108 | To increase the efficiency of encoding, Morse code was designed so that the length of each symbol is approximately inverse to the frequency of occurrence of the character that it represents in text of the English language. Thus the most common letter in English, the letter , has the shortest code: a single "dit". Becau... | https://en.wikipedia.org/wiki?curid=18935 |
4,109 | Early in the nineteenth century, European experimenters made progress with electrical signaling systems, using a variety of techniques including static electricity and electricity from Voltaic piles producing electrochemical and electromagnetic changes. These experimental designs were precursors to practical telegraphi... | https://en.wikipedia.org/wiki?curid=18935 |
4,110 | Following the discovery of electromagnetism by Hans Christian Ørsted in 1820 and the invention of the electromagnet by William Sturgeon in 1824, there were developments in electromagnetic telegraphy in Europe and America. Pulses of electric current were sent along wires to control an electromagnet in the receiving inst... | https://en.wikipedia.org/wiki?curid=18935 |
4,111 | William Cooke and Charles Wheatstone in Britain developed an electrical telegraph that used electromagnets in its receivers. They obtained an English patent in June 1837 and demonstrated it on the London and Birmingham Railway, making it the first commercial telegraph. Carl Friedrich Gauss and Wilhelm Eduard Weber (183... | https://en.wikipedia.org/wiki?curid=18935 |
4,112 | The American artist Samuel Morse, the American physicist Joseph Henry, and mechanical engineer Alfred Vail developed an electrical telegraph system. It needed a method to transmit natural language using only electrical pulses and the silence between them. Around 1837, Morse therefore developed an early forerunner to th... | https://en.wikipedia.org/wiki?curid=18935 |
4,113 | The Morse system for telegraphy, which was first used in about 1844, was designed to make indentations on a paper tape when electric currents were received. Morse's original telegraph receiver used a mechanical clockwork to move a paper tape. When an electrical current was received, an electromagnet engaged an armature... | https://en.wikipedia.org/wiki?curid=18935 |
4,114 | In his earliest design for a code, Morse had planned to transmit only numerals, and to use a codebook to look up each word according to the number which had been sent. However, the code was soon expanded by Alfred Vail in 1840 to include letters and special characters, so it could be used more generally. Vail estimated... | https://en.wikipedia.org/wiki?curid=18935 |
4,115 | In the original Morse telegraph system, the receiver's armature made a clicking noise as it moved in and out of position to mark the paper tape. The telegraph operators soon learned that they could translate the clicks directly into dots and dashes, and write these down by hand, thus making the paper tape unnecessary. ... | https://en.wikipedia.org/wiki?curid=18935 |
4,116 | With the advent of tones produced by radiotelegraph receivers, the operators began to vocalize a dot as "dit", and a dash as "dah", to reflect the sounds of Morse code they heard. To conform to normal sending speed, "dits" which are not the last element of a code became voiced as "di". For example, the letter is voiced... | https://en.wikipedia.org/wiki?curid=18935 |
4,117 | The Morse code, as specified in the current international standard, "International Morse Code Recommendation", ITU-R M.1677-1, was derived from a much-improved proposal by Friedrich Gerke in 1848 that became known as the "Hamburg alphabet". | https://en.wikipedia.org/wiki?curid=18935 |
4,118 | Gerke changed many of the codepoints, in the process doing away with the different length dashes and different inter-element spaces of American Morse, leaving only two coding elements, the dot and the dash. Codes for German umlauted vowels and were introduced. Gerke's code was adopted in Germany and Austria 1851. | https://en.wikipedia.org/wiki?curid=18935 |
4,119 | This finally led to the International Morse code in 1865. The International Morse code adopted most of Gerke's codepoints. The codes for ' and ' were taken from a code system developed by Steinheil. A new codepoint was added for ' since Gerke did not distinguish between ' and '. Changes were also made to ', ', and '. T... | https://en.wikipedia.org/wiki?curid=18935 |
4,120 | In the 1890s, Morse code began to be used extensively for early radio communication before it was possible to transmit voice. In the late 19th and early 20th centuries, most high-speed international communication used Morse code on telegraph lines, undersea cables, and radio circuits. | https://en.wikipedia.org/wiki?curid=18935 |
4,121 | Although previous transmitters were bulky and the spark gap system of transmission was dangerous and difficult to use, there had been some early attempts: In 1910, the U.S. Navy experimented with sending Morse from an airplane. However the first regular aviation radiotelegraphy was on airships, which had space to accom... | https://en.wikipedia.org/wiki?curid=18935 |
4,122 | During World War I, Zeppelin airships equipped with radio were used for bombing and naval scouting, and ground-based radio direction finders were used for airship navigation. Allied airships and military aircraft also made some use of radiotelegraphy. | https://en.wikipedia.org/wiki?curid=18935 |
4,123 | However, there was little aeronautical radio in general use during World War I, and in the 1920s, there was no radio system used by such important flights as that of Charles Lindbergh from New York to Paris in 1927. Once he and the "Spirit of St. Louis" were off the ground, Lindbergh was truly incommunicado and alone. ... | https://en.wikipedia.org/wiki?curid=18935 |
4,124 | Beginning in the 1930s, both civilian and military pilots were required to be able to use Morse code, both for use with early communications systems and for identification of navigational beacons that transmitted continuous two- or three-letter identifiers in Morse code. Aeronautical charts show the identifier of each ... | https://en.wikipedia.org/wiki?curid=18935 |
4,125 | In addition, rapidly moving field armies could not have fought effectively without radiotelegraphy; they moved more quickly than their communications services could put up new telegraph and telephone lines. This was seen especially in the blitzkrieg offensives of the Nazi German Wehrmacht in Poland, Belgium, France (in... | https://en.wikipedia.org/wiki?curid=18935 |
4,126 | Radiotelegraphy using Morse code was vital during World War II, especially in carrying messages between the warships and the naval bases of the belligerents. Long-range ship-to-ship communication was by radio telegraphy, using encrypted messages because the voice radio systems on ships then were quite limited in both t... | https://en.wikipedia.org/wiki?curid=18935 |
4,127 | Morse code was used as an international standard for maritime distress until 1999 when it was replaced by the Global Maritime Distress and Safety System. When the French Navy ceased using Morse code on January 31, 1997, the final message transmitted was "Calling all. This is our last cry before our eternal silence." | https://en.wikipedia.org/wiki?curid=18935 |
4,128 | In the United States the final commercial Morse code transmission was on July 12, 1999, signing off with Samuel Morse's original 1844 message, , and the prosign ("end of contact"). | https://en.wikipedia.org/wiki?curid=18935 |
4,129 | The United States Coast Guard has ceased all use of Morse code on the radio, and no longer monitors any radio frequencies for Morse code transmissions, including the international medium frequency (MF) distress frequency of However, the Federal Communications Commission still grants commercial radiotelegraph operator l... | https://en.wikipedia.org/wiki?curid=18935 |
4,130 | Morse code speed is measured in words per minute () or characters per minute (). Characters have differing lengths because they contain differing numbers of "dits" and "dahs". Consequently, words also have different lengths in terms of dot duration, even when they contain the same number of characters. For this reason,... | https://en.wikipedia.org/wiki?curid=18935 |
4,131 | In addition to knowing, understanding, and being able to copy the standard written alpha-numeric and punctuation characters or symbols at high speeds, skilled high speed operators must also be fully knowledgeable of all of the special unwritten Morse code symbols for the standard Prosigns for Morse code and the meaning... | https://en.wikipedia.org/wiki?curid=18935 |
4,132 | International contests in code copying are still occasionally held. In July 1939 at a contest in Asheville, North Carolina in the United States Ted R. McElroy W1JYN set a still-standing record for Morse copying, 75.2 . Pierpont (2004) also notes that some operators may have passed 100 . By this time, they are "hearing"... | https://en.wikipedia.org/wiki?curid=18935 |
4,133 | Today among amateur operators there are several organizations that recognize high-speed code ability, one group consisting of those who can copy Morse at 60 . Also, Certificates of Code Proficiency are issued by several amateur radio societies, including the American Radio Relay League. Their basic award starts at 10 ... | https://en.wikipedia.org/wiki?curid=18935 |
4,134 | Through May 2013, the First, Second, and Third Class (commercial) Radiotelegraph Licenses using code tests based upon the standard word were still being issued in the United States by the Federal Communications Commission. The First Class license required 20 code group and 25 text code proficiency, the others 16 cod... | https://en.wikipedia.org/wiki?curid=18935 |
4,135 | Currently, only one class of license, the Radiotelegraph Operator License, is issued. This is granted either when the tests are passed or as the Second and First are renewed and become this lifetime license. For new applicants, it requires passing a written examination on electronic theory and radiotelegraphy practices... | https://en.wikipedia.org/wiki?curid=18935 |
4,136 | Morse code has been in use for more than 160 years — longer than any other electrical coding system. What is called Morse code today is actually somewhat different from what was originally developed by Vail and Morse. The Modern International Morse code, or "continental code", was created by Friedrich Clemens Gerke in ... | https://en.wikipedia.org/wiki?curid=18935 |
4,137 | In aviation, pilots use radio navigation aids. To ensure that the stations the pilots are using are serviceable, the stations transmit a set of identification letters (usually a two-to-five-letter version of the station name) in Morse code. Station identification letters are shown on air navigation charts. For example,... | https://en.wikipedia.org/wiki?curid=18935 |
4,138 | International Morse code today is most popular among amateur radio operators, in the mode commonly referred to as "continuous wave" or "CW". (This name was chosen to distinguish it from the damped wave emissions from spark transmitters, not because the transmission is continuous.) Other keying methods are available in ... | https://en.wikipedia.org/wiki?curid=18935 |
4,139 | The original amateur radio operators used Morse code exclusively since voice-capable radio transmitters did not become commonly available until around 1920. Until 2003, the International Telecommunication Union mandated Morse code proficiency as part of the amateur radio licensing procedure worldwide. However, the Worl... | https://en.wikipedia.org/wiki?curid=18935 |
4,140 | Until 1991, a demonstration of the ability to send and receive Morse code at a minimum of five words per minute () was required to receive an amateur radio license for use in the United States from the Federal Communications Commission. Demonstration of this ability was still required for the privilege to use the HF ba... | https://en.wikipedia.org/wiki?curid=18935 |
4,141 | While voice and data transmissions are limited to specific amateur radio bands under U.S. rules, Morse code is permitted on all amateur bands — LF, MF, HF, VHF, and UHF. In some countries, certain portions of the amateur radio bands are reserved for transmission of Morse code signals only. | https://en.wikipedia.org/wiki?curid=18935 |
4,142 | Because Morse code transmissions employ an on-off keyed radio signal, it requires less complex transmission equipment than other forms of radio communication. Morse code also requires less signal bandwidth than voice communication, typically 100–150 Hz, compared to the roughly 2,400 Hz used by single-sideband voice, al... | https://en.wikipedia.org/wiki?curid=18935 |
4,143 | Morse code is usually received as a high-pitched audio tone, so transmissions are easier to copy than voice through the noise on congested frequencies, and it can be used in very high noise / low signal environments. The fact that the transmitted power is concentrated into a very limited bandwidth makes it possible to ... | https://en.wikipedia.org/wiki?curid=18935 |
4,144 | The relatively limited speed at which Morse code can be sent led to the development of an extensive number of abbreviations to speed communication. These include prosigns, Q codes, and a set of Morse code abbreviations for typical message components. For example, ' is broadcast to be interpreted as "seek you" (I'd like... | https://en.wikipedia.org/wiki?curid=18935 |
4,145 | Although the traditional telegraph key (straight key) is still used by some amateurs, the use of mechanical semi-automatic keyers (known as "bugs") and of fully automatic electronic keyers is prevalent today. Software is also frequently employed to produce and decode Morse code radio signals. The ARRL has a readability... | https://en.wikipedia.org/wiki?curid=18935 |
4,146 | Radio navigation aids such as VORs and NDBs for aeronautical use broadcast identifying information in the form of Morse Code, though many VOR stations now also provide voice identification. Warships, including those of the U.S. Navy, have long used signal lamps to exchange messages in Morse code. Modern use continues, ... | https://en.wikipedia.org/wiki?curid=18935 |
4,147 | Automatic Transmitter Identification System (ATIS) uses Morse code to identify uplink sources of analog satellite transmissions. | https://en.wikipedia.org/wiki?curid=18935 |
4,148 | Many amateur radio repeaters identify with Morse, even though they are used for voice communications. | https://en.wikipedia.org/wiki?curid=18935 |
4,149 | An important application is signalling for help through SOS, "". This can be sent many ways: keying a radio on and off, flashing a mirror, toggling a flashlight, and similar methods. The SOS signal is not sent as three separate characters; rather, it is a prosign , and is keyed without gaps between characters. | https://en.wikipedia.org/wiki?curid=18935 |
4,150 | Some Nokia mobile phones offer an option to alert the user of an incoming text message with the Morse tone "" (representing SMS or Short Message Service). In addition, applications are now available for mobile phones that enable short messages to be input in Morse Code. | https://en.wikipedia.org/wiki?curid=18935 |
4,151 | Morse code has been employed as an assistive technology, helping people with a variety of disabilities to communicate. For example, the Android operating system versions 5.0 and higher allow users to input text using Morse Code as an alternative to a keypad or handwriting recognition. | https://en.wikipedia.org/wiki?curid=18935 |
4,152 | Morse can be sent by persons with severe motion disabilities, as long as they have some minimal motor control. An original solution to the problem that caretakers have to learn to decode has been an electronic typewriter with the codes written on the keys. Codes were sung by users; see the voice typewriter employing Mo... | https://en.wikipedia.org/wiki?curid=18935 |
4,153 | Morse code can also be translated by computer and used in a speaking communication aid. In some cases, this means alternately blowing into and sucking on a plastic tube ("sip-and-puff" interface). An important advantage of Morse code over row column scanning is that once learned, it does not require looking at a displa... | https://en.wikipedia.org/wiki?curid=18935 |
4,154 | In one case reported in the radio amateur magazine "QST", an old shipboard radio operator who had a stroke and lost the ability to speak or write could communicate with his physician (a radio amateur) by blinking his eyes in Morse. Two examples of communication in intensive care units were also published in "QST magazi... | https://en.wikipedia.org/wiki?curid=18935 |
4,155 | Morse code can be transmitted in a number of ways: originally as electrical pulses along a telegraph wire, but also as an audio tone, a radio signal with short and long tones, or as a mechanical, audible, or visual signal (e.g. a flashing light) using devices like an Aldis lamp or a heliograph, a common flashlight, or ... | https://en.wikipedia.org/wiki?curid=18935 |
4,156 | Morse code is transmitted using just two states (on and off). Historians have called it the first digital code. Morse code may be represented as a binary code, and that is what telegraph operators do when transmitting messages. Working from the above ITU definition and further defining a bit as a dot time, a Morse code... | https://en.wikipedia.org/wiki?curid=18935 |
4,157 | Note that the marks and gaps alternate: "Dits" and "dahs" are always separated by one of the gaps, and that the gaps are always separated by a "dit" or a "dah". | https://en.wikipedia.org/wiki?curid=18935 |
4,158 | Morse messages are generally transmitted by a hand-operated device such as a telegraph key, so there are variations introduced by the skill of the sender and receiver — more experienced operators can send and receive at faster speeds. In addition, individual operators differ slightly, for example, using slightly longer... | https://en.wikipedia.org/wiki?curid=18935 |
4,159 | The very long time constants of 19th and early 20th century submarine communications cables required a different form of Morse signalling. Instead of keying a voltage on and off for varying times, the dits and dahs were represented by two polarities of voltage impressed on the cable, for a uniform time. | https://en.wikipedia.org/wiki?curid=18935 |
4,160 | Below is an illustration of timing conventions. The phrase , in Morse code format, would normally be written something like this, where represents "dahs" and represents "dits": | https://en.wikipedia.org/wiki?curid=18935 |
4,161 | Next is the exact conventional timing for this phrase, with representing "signal on", and representing "signal off", each for the time length of exactly one dit: | https://en.wikipedia.org/wiki?curid=18935 |
4,162 | Morse code is often spoken or written with "dah" for dashes, "dit" for dots located at the end of a character, and "di" for dots located at the beginning or internally within the character. Thus, the following Morse code sequence: | https://en.wikipedia.org/wiki?curid=18935 |
4,163 | There is little point in learning to read Morse as above; rather, the of all of the letters and symbols need to be learned, for both sending and receiving. | https://en.wikipedia.org/wiki?curid=18935 |
4,164 | All Morse code elements depend on the dot length. A "dah" is the length of 3 dits (with no gaps between), and spacings are specified in number of "dit" lengths. An unambiguous method of specifying the transmission speed is to specify the "dit" duration as, for example, 50 milliseconds. | https://en.wikipedia.org/wiki?curid=18935 |
4,165 | Specifying the "dit" duration is, however, not the common practice. Usually, speeds are stated in words per minute. That introduces ambiguity because words have different numbers of characters, and characters have different "dit" lengths. It is not immediately clear how a specific word rate determines the "dit" duratio... | https://en.wikipedia.org/wiki?curid=18935 |
4,166 | Some method to standardize the transformation of a word rate to a "dit" duration is useful. A simple way to do this is to choose a "dit" duration that would send a typical word the desired number of times in one minute. If, for example, the operator wanted a character speed of 13 words per minute, the operator would ch... | https://en.wikipedia.org/wiki?curid=18935 |
4,167 | The typical word thus determines the dot length. It is common to assume that a word is 5 characters long. There are two common typical words: ' and '. ' mimics a word rate that is typical of natural language words and reflects the benefits of Morse code's shorter code durations for common characters such as ' and '. ' ... | https://en.wikipedia.org/wiki?curid=18935 |
4,168 | Because Morse code is usually sent by hand, it is unlikely that an operator could be that precise with the dot length, and the individual characteristics and preferences of the operators usually override the standards. | https://en.wikipedia.org/wiki?curid=18935 |
4,169 | For commercial radiotelegraph licenses in the United States, the Federal Communications Commission specifies tests for Morse code proficiency in words per minute and in code groups per minute. The FCC specifies that a word is 5 characters long. The Commission specifies Morse code test elements at 16 code groups per min... | https://en.wikipedia.org/wiki?curid=18935 |
4,170 | While the Federal Communications Commission no longer requires Morse code for amateur radio licenses, the old requirements were similar to the requirements for commercial radiotelegraph licenses. | https://en.wikipedia.org/wiki?curid=18935 |
4,171 | A difference between amateur radio licenses and commercial radiotelegraph licenses is that commercial operators must be able to receive code groups of random characters along with plain language text. For each class of license, the code group speed requirement is slower than the plain language text requirement. For exa... | https://en.wikipedia.org/wiki?curid=18935 |
4,172 | Based upon a 50 dot duration standard word such as , the time for one "dit" duration or one unit can be computed by the formula: | https://en.wikipedia.org/wiki?curid=18935 |
4,173 | High-speed telegraphy contests are held; according to the "Guinness Book of Records" in June 2005 at the International Amateur Radio Union's 6th World Championship in High Speed Telegraphy in Primorsko, Bulgaria, Andrei Bindasov of Belarus transmitted 230 Morse code marks of mixed text in one minute. | https://en.wikipedia.org/wiki?curid=18935 |
4,174 | Sometimes, especially while teaching Morse code, the timing rules above are changed so two different speeds are used: A character speed and a text speed. The character speed is how fast each individual letter is sent. The text speed is how fast the entire message is sent. For example, individual characters may be sent ... | https://en.wikipedia.org/wiki?curid=18935 |
4,175 | Using different character and text speeds is, in fact, a common practice, and is used in the Farnsworth method of learning Morse code. | https://en.wikipedia.org/wiki?curid=18935 |
4,176 | People learning Morse code using the "Farnsworth method" are taught to send and receive letters and other symbols at their full target speed, that is with normal relative timing of the "dits", "dahs", and spaces within each symbol for that speed. The Farnsworth method is named for Donald R. "Russ" Farnsworth, also know... | https://en.wikipedia.org/wiki?curid=18935 |
4,177 | Another popular teaching method is the Koch method, invented in 1935 by the German engineer and former stormtrooper Ludwig Koch, which uses the full target speed from the outset but begins with just two characters. Once strings containing those two characters can be copied with 90% accuracy, an additional character is ... | https://en.wikipedia.org/wiki?curid=18935 |
4,178 | In North America, many thousands of individuals have increased their code recognition speed (after initial memorization of the characters) by listening to the regularly scheduled code practice transmissions broadcast by W1AW, the American Radio Relay League's headquarters station., the United States military taught Mor... | https://en.wikipedia.org/wiki?curid=18935 |
4,179 | Visual mnemonic charts have been devised over the ages. Baden-Powell included one in the Girl Guides handbook in 1918. | https://en.wikipedia.org/wiki?curid=18935 |
4,180 | In the United Kingdom, many people learned the Morse code by means of a series of words or phrases that have the same rhythm as a Morse character. For instance, ' in Morse is which can be memorized by the phrase "God Save the Queen", and the Morse for ' is which can be memorized as "Did she like it?" | https://en.wikipedia.org/wiki?curid=18935 |
4,181 | Prosigns for Morse code are special (usually) unwritten procedural signals or symbols that are used to indicate changes in communications protocol status or white space text formatting actions. | https://en.wikipedia.org/wiki?curid=18935 |
4,182 | The symbols [!], [$], and [&] are not defined inside the official ITU-R "International Morse Code Recommendation", but informal conventions for them exist. (The [@] symbol was formally added in 2004.) | https://en.wikipedia.org/wiki?curid=18935 |
4,183 | The typical tactic for creating Morse codes for non-Latin alphabetic scripts has been to begin by simply using the International Morse codes used for letters whose sound matches the sound of the local alphabet. Because Gerke's code was in official use in central Europe, and included many non-Latin characters, none of w... | https://en.wikipedia.org/wiki?curid=18935 |
4,184 | The usual method has been to first transliterate the sounds represented by the International, and second the Gerke code into the local alphabet, hence Greek, Hebrew, Russian, and Ukrainian Morse codes. If more codes are needed, one can either invent a new code or convert an otherwise unused code from either code set to... | https://en.wikipedia.org/wiki?curid=18935 |
4,185 | For Russian and Bulgarian, Russian Morse code is used to map the Cyrillic characters to four-element codes. Many of the characters are encoded the same way (A, O, E, I, T, M, N, R, K, etc.). The Bulgarian alphabet contains 30 characters, which exactly match all possible combinations of 1, 2, 3, and 4 "dits" and "dahs" ... | https://en.wikipedia.org/wiki?curid=18935 |
4,186 | Non-alphabetic scripts require more radical adaption. Japanese Morse code (Wabun code) has a separate encoding for kana script; although many of the codes are used for International Morse, their sounds are mostly unrelated. The Japanese / Wabun code includes special prosigns for switching back-and-forth from Internatio... | https://en.wikipedia.org/wiki?curid=18935 |
4,187 | For Chinese, Chinese telegraph code is used to map Chinese characters to four-digit codes and send these digits out using standard Morse code. Korean Morse code uses the SKATS mapping, originally developed to allow Korean to be typed on western typewriters. SKATS maps hangul characters to arbitrary letters of the Latin... | https://en.wikipedia.org/wiki?curid=18935 |
4,188 | During early World War I (1914–1916), Germany briefly experimented with 'dotty' and 'dashy' Morse, in essence adding a dot or a dash at the end of each Morse symbol. Each one was quickly broken by Allied SIGINT, and standard Morse was restored by Spring 1916. Only a small percentage of Western Front (North Atlantic and... | https://en.wikipedia.org/wiki?curid=18935 |
4,189 | Decoding software for Morse code ranges from software-defined wide-band radio receivers, coupled to the Reverse Beacon Network, which decodes signals and detects messages on ham bands, to smartphone applications. | https://en.wikipedia.org/wiki?curid=18935 |
4,190 | Software is a set of computer programs and associated documentation and data. This is in contrast to hardware, from which the system is built and which actually performs the work. | https://en.wikipedia.org/wiki?curid=5309 |
4,191 | At the lowest programming level, executable code consists of machine language instructions supported by an individual processor—typically a central processing unit (CPU) or a graphics processing unit (GPU). Machine language consists of groups of binary values signifying processor instructions that change the state of t... | https://en.wikipedia.org/wiki?curid=5309 |
4,192 | The majority of software is written in high-level programming languages. They are easier and more efficient for programmers because they are closer to natural languages than machine languages. High-level languages are translated into machine language using a compiler or an interpreter or a combination of the two. Softw... | https://en.wikipedia.org/wiki?curid=5309 |
4,193 | An algorithm for what would have been the first piece of software was written by Ada Lovelace in the 19th century, for the planned Analytical Engine. She created proofs to show how the engine would calculate Bernoulli numbers. Because of the proofs and the algorithm, she is considered the first computer programmer. | https://en.wikipedia.org/wiki?curid=5309 |
4,194 | The first theory about software, prior to the creation of computers as we know them today, was proposed by Alan Turing in his 1936 essay, "On Computable Numbers, with an Application to the Entscheidungsproblem" (decision problem). This eventually led to the creation of the academic fields of computer science and softwa... | https://en.wikipedia.org/wiki?curid=5309 |
4,195 | In 2000, Fred Shapiro, a librarian at the Yale Law School, published a letter revealing that John Wilder Tukey's 1958 paper "The Teaching of Concrete Mathematics" contained the earliest known usage of the term "software" found in a search of JSTOR's electronic archives, predating the OED's citation by two years. This l... | https://en.wikipedia.org/wiki?curid=5309 |
4,196 | Programming tools are also software in the form of programs or applications that developers use to create, debug, maintain, or otherwise support software. | https://en.wikipedia.org/wiki?curid=5309 |
4,197 | Software is written in one or more programming languages; there are many programming languages in existence, and each has at least one implementation, each of which consists of its own set of programming tools. These tools may be relatively self-contained programs such as compilers, debuggers, interpreters, linkers, an... | https://en.wikipedia.org/wiki?curid=5309 |
4,198 | People who use modern general purpose computers (as opposed to embedded systems, analog computers and supercomputers) usually see three layers of software performing a variety of tasks: platform, application, and user software. | https://en.wikipedia.org/wiki?curid=5309 |
4,199 | Computer software has to be "loaded" into the computer's storage (such as the hard drive or memory). Once the software has loaded, the computer is able to "execute" the software. This involves passing instructions from the application software, through the system software, to the hardware which ultimately receives the ... | https://en.wikipedia.org/wiki?curid=5309 |
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