Qwerty Keyboard Layout Pdf

[Ashlie Mealey]

TheQWERTY layout was devised and created in the early 1870s by Christopher Latham Sholes, a newspaper editor and printer who lived in Kenosha, Wisconsin. In October 1867, Sholes filed a patent application for his early writing machine he developed with the assistance of his friends Carlos Glidden and Samuel W. Soul.[1]

After they purchased the device, Remington made several adjustments, creating a keyboard with essentially the modern QWERTY layout. These adjustments included placing the "R" key in the place previously allotted to the period key. Apocryphal claims that this change was made to let salesmen impress customers by pecking out the brand name "TYPE WRITER QUOTE" from one keyboard row is not formally substantiated.[2] Vestiges of the original alphabetical layout remained in the "home row" sequence DFGHJKL.[4]

The QWERTY layout depicted in Sholes's 1878 patent is slightly different from the modern layout, most notably in the absence of the numerals 0 and 1, with each of the remaining numerals shifted one position to the left of their modern counterparts. The letter M is located at the end of the third row to the right of the letter L rather than on the fourth row to the right of the N, the letters X and C are reversed, and most punctuation marks are in different positions or are missing entirely.[6] 0 and 1 were omitted to simplify the design and reduce the manufacturing and maintenance costs; they were chosen specifically because they were "redundant" and could be recreated using other keys. Typists who learned on these machines learned the habit of using the uppercase letter I (or lowercase letter L) for the digit one, and the uppercase O for the zero.[7]

In early designs, some characters were produced by printing two symbols with the carriage in the same position. For instance, the exclamation point, which shares a key with the numeral 1 on post-mechanical keyboards, could be reproduced by using a three-stroke combination of an apostrophe, a backspace, and a period. A semicolon (;) was produced by printing a comma (,) over a colon (:). As the backspace key is slow in simple mechanical typewriters (the carriage was heavy and optimized to move in the opposite direction), a more professional approach was to block the carriage by pressing and holding the space bar while printing all characters that needed to be in a shared position. To make this possible, the carriage was designed to advance only after releasing the space bar.

There were no particular technological requirements for the QWERTY layout,[2] since at the time there were ways to make a typewriter without the "up-stroke" typebar mechanism that had required it to be devised. Not only were there rival machines with "down-stroke" and "front stroke" positions that gave a visible printing point, the problem of typebar clashes could be circumvented completely: examples include Thomas Edison's 1872 electric print-wheel device which later became the basis for Teletype machines; Lucien Stephen Crandall's typewriter (the second to come onto the American market in 1883) whose type was arranged on a cylindrical sleeve; the Hammond typewriter of 1885 which used a semi-circular "type-shuttle" of hardened rubber (later light metal); and the Blickensderfer typewriter of 1893 which used a type wheel. The early Blickensderfer's "Ideal" keyboard was also non-QWERTY, instead having the sequence "DHIATENSOR" in the home row, these 10 letters being capable of composing 70% of the words in the English language.[9]

Alternating hands while typing is a desirable trait in a keyboard design. While one hand types a letter, the other hand can prepare to type the next letter, making the process faster and more efficient. In the QWERTY layout many more words can be spelled using only the left hand than the right hand. Thousands of English words can be spelled using only the left hand, while only a couple of hundred words can be typed using only the right hand[10] (the three most frequent letters in the English language, ETA, are all typed with the left hand). In addition, more typing strokes are done with the left hand in the QWERTY layout. This is helpful for left-handed people but disadvantageous for right-handed people.

The first computer terminals such as the Teletype were typewriters that could produce and be controlled by various computer codes. These used the QWERTY layouts and added keys such as escape Esc which had special meanings to computers. Later keyboards added function keys and arrow keys. Since the standardization of personal computers and Windows after the 1980s, most full-sized computer keyboards have followed this standard (see drawing at right). This layout has a separate numeric keypad for data entry at the right, 12 function keys across the top, and a cursor section to the right and center with keys for Insert, Delete, Home, End, Page Up, and Page Down with cursor arrows in an inverted-T shape.[14]

QWERTY was designed for English, a language with accents ('diacritics') appearing only in a few words of foreign origin. The standard US keyboard has no provision for these at all; the need was later met by the so-called "US-International" keyboard mapping, which uses "dead keys" to type accents without having to add more physical keys. (The same principle is used in the standard US keyboard layout for macOS, but in a different way). Most European (including UK) keyboards for PCs have an AltGr key ('Alternative Graphics' key,[a] replaces the right Alt key) that enables easy access to the most common diacritics used in the territory where sold. For example, default keyboard mapping for the UK/Ireland keyboard has the diacritics used in Irish but these are rarely printed on the keys; but to type the accents used in Welsh and Scots Gaelic requires the use of a "UK Extended" keyboard mapping and the dead key or compose key method. This arrangement applies to Windows, ChromeOS and Linux; macOS computers have different techniques. The US International and UK Extended mappings provide many of the diacritics needed for students of other European languages.

Minor changes to the arrangement are made for other languages. There are a large number of different keyboard layouts used for different languages written in Latin script. They can be divided into three main families according to where the Q, A, Z, M, and Y keys are placed on the keyboard. These are usually named after the first six letters, for example this QWERTY layout and the AZERTY layout.

In this section you will also find keyboard layouts that include some additional symbols of other languages. But they are different from layouts that were designed with the goal to be usable for multiple languages (see Multilingual variants).

English-speaking Canadians have traditionally used the same keyboard layout as in the United States, unless they are in a position where they have to write French on a regular basis. French-speaking Canadians respectively have favoured the Canadian French keyboard layout (see French (Canada), below).

The BS 4822:1994 standard did not make any use of the AltGr key and lacked support for any non-ASCII characters other than and . It also assigned a key for the non-ASCII character broken bar , but lacked one for the far more commonly used ASCII character vertical bar . It also lacked support for various diacritics used in the Welsh alphabet, and the Scots Gaelic alphabet; and also is missing the letter yogh, ȝ, used very rarely in the Scots language. Therefore, various manufacturers have modified or extended the BS 4822 standard:

Support for the diacritics needed for Scots Gaelic and Welsh was added to Windows and ChromeOS using a "UK-extended" setting (see below); Linux and X11 systems have an explicit or reassigned Compose key for this purpose.

US keyboards are used not only in the United States, but also in many other English-speaking places (except UK and Ireland), including India, Australia, Anglophone Canada, Hong Kong, New Zealand, South Africa, Malaysia, Singapore, Philippines, and Indonesia that uses the same 26-letter alphabets as English. In many other English-speaking jurisdictions (e.g., Canada, Australia, the Caribbean nations, Hong Kong, Malaysia, India, Pakistan, Bangladesh, Singapore, New Zealand, and South Africa), local spelling sometimes conforms more closely to British English usage, although these nations decided to use a US English keyboard layout. Until Windows 8 and later versions, when Microsoft separated the settings, this had the undesirable side effect of also setting the language to US English, rather than the local orthography.

The US keyboard layout has a second Alt instead of the AltGr key and does not use any dead keys; this makes it inefficient for all but a handful of languages. On the other hand, the US keyboard layout (or the similar UK layout) is occasionally used by programmers in countries where the keys for [{ are located in less convenient positions on the locally customary layout.[19]

Two keyboard layouts that are based on Qwerty are used in Arabic-speaking countries. Microsoft designate them as Arabic (101) and Arabic (102).In both the number line is identical to the American layout, beside ( ) being mirrored, and not including the key to the left of 1. The \ key on the right side of the keyboard is also the same. could also be produced by shifting the key on the left side of the keyboard. "? are produced by shifting the same keys, but ? is mirrored to . In Arabic (102) it's true also for which are again mirrored.Finally, , instead of being the normal output of their keys, are produced by shifting the same keys.[25]

The typewriter came to the Czech-speaking area in the late 19th century, when it was part of Austria-Hungary where German was the dominant language of administration. Therefore, Czech typewriters have the QWERTZ layout.

However, with the introduction of imported computers, especially since the 1990s, the QWERTY keyboard layout is frequently used for computer keyboards. The Czech QWERTY layout differs from QWERTZ in that the characters (e.g. @$& and others) missing from the Czech keyboard are accessible with AltGr on the same keys where they are located on an American keyboard. In Czech QWERTZ keyboards the positions of these characters accessed through AltGr differs.

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