ASCII Reference Guide - Free

The American Standard Code for Information Interchange (ASCII) is a character-encoding scheme based on the ordering of the English alphabet. ASCII codes represent text in computers, communications equipment, and other devices that use text.
Character tables:

◼ ASCII tablethe
128 ASCII character table

◼ ASCII extended sets
the 256 character ASCII extended sets used in the IBM PC (MS-DOS) or in the Apple Mac

◼ ANSI table (ISO 8859-1)
the 256 ANSI character table used by Windows