Editing ANSI escape code (section)

== C0 control codes ==
Almost all users assume some functions of some single-byte characters. Initially defined as part of ASCII, the default C0 control code set is now defined in ISO 6429 (ECMA-48), making it part of the same standard as the C1 set invoked by the ANSI escape sequences (although [[ISO 2022]] allows the ISO 6429 C0 set to be used without the ISO 6429 C1 set, and ''vice versa'', provided that 0x1B is always ESC). This is used to shorten the amount of data transmitted, or to perform some functions that are unavailable from escape sequences:

{| class="wikitable"
|+ Popular C0 control codes (not an exhaustive list)
|-
! [[Caret notation|^]] !!C0!!Abbr!!Name!!Effect
|- id=BEL
| {{tt|^G}} || 0x07 || {{tt|BEL}} || Bell || Makes an audible noise.
|- id=BS
| {{tt|^H}} || 0x08 || {{tt|BS}} || Backspace || Moves the cursor left (but may "backwards wrap" if cursor is at start of line).
|- id=HT
| {{tt|^I}} || 0x09 || {{tt|HT}} || Tab || Moves the cursor right to next tab stop.
|- id=LF
| {{tt|^J}} || 0x0A || {{tt|LF}} || Line Feed || Moves to next line, scrolls the display up if at bottom of the screen. Usually does not move horizontally, though programs should not rely on this.
|- id=FF
| {{tt|^L}} || 0x0C || {{tt|FF}} || Form Feed || Move a printer to top of next page. Usually does not move horizontally, though programs should not rely on this. Effect on video terminals varies.
|- id=CR
| {{tt|^M}} || 0x0D || {{tt|CR}} || {{nobr|Carriage Return}} || Moves the cursor to column zero.
|- id=ESC
| {{tt|^[}} || 0x1B || {{tt|{{visible anchor|ESC}}}} || Escape || Starts all the escape sequences
|}

Escape sequences vary in length. The general format for an ANSI-compliant escape sequence is defined by [[ANSI X3.41]] (equivalent to ECMA-35 or ISO/IEC 2022).<ref name="ECMA-35"/>{{Rp|13.1}} The escape sequences consist only of bytes in the range {{tt|0x20—0x7F}} (all the non-control ASCII characters), and can be parsed without looking ahead. The behavior when a control character, a byte with the high bit set, or a byte that is not part of any valid sequence, is encountered before the end is undefined.