ASCII

From Computer History Wiki
Revision as of 08:53, 18 June 2020 by ForOldHack (talk | contribs) (added a sentence of clarity: and possible expansion.)
Jump to navigationJump to search

ASCII (an acronym for American Standard Code for Information Interchange) is an encoding for various glyphs (written forms such as letters, numbers, etc) into 7-bit numeric form.

ASCII was developed from telegraph code. Its first commercial use was as a seven-bit teleprinter code promoted by Bell data services. ... Originally based on the English alphabet, ASCII encodes 128 specified characters into seven-bit integers, Later, it was adopted for use in tele-printers, terminals and personal computers such as the Apple II, and the IBM PC. IBM extended the character set with a separate set of glyphs used for line drawing.

The supported set for ASCII includes not only numbers, letters (upper- and lower-case) but also punctuation, and other special-purpose characters (from then-common ones like '@', '#', etc, to others that ASCII has made popular - '^', '|', etc). It also includes non-printing characters used for control of printing terminals - tab, line feed, carriage return, etc.

IBM had its own encoding standard, EBCDIC, which ASCII has gradually superseded.

ASCII also superseded an earlier widespread encoding, SIXBIT, which allowed 6 characters to be carried in the then-common 36-bit words common on many computers, but only supported upper-case characters.

ASCII was derived from Bodit