ASCII characters

ASCII is a code set containing 128 code points (0x00 through 0x7F). The ASCII character set contains control characters, punctuation marks, digits, and the uppercase and lowercase English alphabet. Several 8-bit code sets incorporate ASCII as a proper subset. However, throughout this document, ASCII refers to 7-bit-only code sets. To emphasize this, it is referred to as 7-bit ASCII. The 7-bit ASCII code set is a proper subset of all supported code sets and is referred to as the portable character set.