Data-transmission code used to represent both text (letters, numbers, punctuation marks) and noninput device commands (control characters) for electronic exchange and storage. Standard ASCII uses a string of 7 bits (binary digits) for each symbol and can thus represent 27 = 128 characters. Extended ASCII uses an 8-bit encoding system and can thus represent 28 = 256 characters. While ASCII is still found in legacy data, Unicode, with 8-, 16-, and 32-bit versions, has become standard for modern operating systems and browsers. In particular, the 32-bit version now supports all of the characters in every major language.
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