# ASCII Character Set for Linux* and macOS*

This topic describes the ASCII character set that is available on Linux* and macOS operating systems.

The ASCII character set contains characters with decimal values 0 through 127. The first half of each of the numbered columns identifies the character as you would enter it on a terminal or as you would see it on a printer. Except for SP and HT, the characters with names are nonprintable. In the figure, the characters with names are defined as follows:

NUL | Null | DC1 | Device Control 1 (XON)
SOH | Start of Heading | DC2 | Device Control 2
STX | Start of Text | DC3 | Device Control 1 (XOFF)
ETX | End of Text | DC4 | Device Control 4
EOT | End of Transmission | NAK | Negative Acknowledge
ENQ | Enquiry | SYN | Synchronous Idle
ACK | Acknowledge | ETB | End of Transmission Block
BEL | Bell | CAN | Cancel
BS | Backspace | EM | End of Medium
HT | Horizontal Tab | SUB | Substitute
LF | Line Feed | ESC | Escape
VT | Vertical Tab | FS | File Separator
FF | Form Feed | GS | Group Separator
CR | Carriage Return | RS | Record Separator
SO | Shift Out | US | Unit Separator
SI | Shift In | SP | Space
DLE | Data Link Escape | DEL | Delete

The remaining half of each column identifies the character by the binary value of the byte; the value is stated in three radixes—octal, decimal, and hexadecimal. For example, the uppercase letter A has, under ASCII conventions, a storage value of hexadecimal 41 (a bit configuration of 01000001), equivalent to 101 in octal notation and 65 in decimal notation.

ASCII Character Set (L*X, M*X)
Parent topic: Additional Character Sets