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This is a list of some binary codes that are (or have been) used to represent text as a sequence of binary digits "0" and "1". Fixed-width binary codes use a set number of bits to represent each character in the text, while in variable-width binary codes, the number of bits may vary from character to character. five binary thing A number of different five-bit codes were used for early punched tape systems. Five bits per character only allows for 32 different characters, so many of the five bit codes used two sets of characters per value referred to as FIGS (figures) and LTRS (letters), and reserved two characters to switch between these sets. This effectively allowed the use of 60 characters. The following early computer systems each used their own five-bit codes: * J. Lyons and Co. LEO (Lyon's Electronic Office) * English Electric DEUCE * University of Illinois at Urbana-Champaign ILLIAC * ZEBRA * EMI 1100 * Ferranti Mercury, Pegasus, and Orion systems 〔http://ferranti-orion.co.uk/pages/section4/4-3.htm〕 More general five-bit standard codes are: * International Telegraph Alphabet No 1 (ITA1) - Also commonly referred to as Baudot code〔http://www.nadcomm.com/fiveunit/fiveunits.htm Five-unit Codes by Alan G Hobbs〕 * International Telegraph Alphabet No 2 (ITA2) - Also commonly referred to as Murray code 〔http://www.nadcomm.com/fiveunit/fiveunits.htm Five-unit Codes by Alan G Hobbs〕〔http://www.baudot.net/docs/smith--teletype-codes.pdf〕 * American Teletypewriter code (USTTY) - A variant of ITA2 used in the USA 〔http://www.baudot.net/docs/smith--teletype-codes.pdf〕 * DIN 66006 - Developed for presentation of ALGOL/ALCOR programs on paper tape and punch cards Finally, the steganographic code commonly known as Bacon's cipher uses groups of 5 binary valued elements to represent letters of the alphabet. == Six-bit binary codes == Six bits per character allows 64 distinct characters to be represented. Examples of six-bit binary codes are: * International Telegraph Alphabet No 4 (ITA4) 〔http://www.quadibloc.com/crypto/tele03.htm〕 * Six-bit BCD (Binary Coded Decimal), used by early mainframe computers. * Six-bit ASCII subset of the primitive seven-bit ASCII * Braille - Braille characters are represented using six dot positions, arranged in a rectangle. Each position may contain a raised dot or not, so Braille can be considered to be a six-bit binary code. See also: Six-bit character codes 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「List of binary codes」の詳細全文を読む スポンサード リンク
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