ASCII (American Standard Code for Information Interchange) is a character encoding standard using 7-bit to represent 128 characters used by computers for converting letters, numbers, punctuation, and control codes into digital form.

The first 33 ASCII code points are non-printing control codes including the carriage return, line feed, tab, and several obsolete non-printable codes stemming from its origin of representing telegraph codes. The other 95 are printable characters, including digits (0-9), lowercase (a-z) and uppercase (A-Z) letters, and punctuation symbols.

Many computer systems instead use Unicode, which has millions of code points, but the first 128 of these are the same as the ASCII set. UTF-8 superseded ASCII on the Web in 2007.

See also