C0 Controls

Single-byte controls in 0x00–0x1F and 0x7F, plus the Fe-class two-byte introducers built on ESC. These are the most primitive terminal controls — backspace, line feed, carriage return, bell.

The C0 set

Byte	Mnemonic	Name
0x07	BEL	Bell — see Notifications
0x08	BS	Backspace — move cursor one cell left
0x09	HT	Horizontal Tab
0x0A	LF	Line Feed
0x0B	VT	Vertical Tab (treated as LF by default)
0x0C	FF	Form Feed (treated as LF by default)
0x0D	CR	Carriage Return
0x0E	SO	Shift Out — switch to G1 character set
0x0F	SI	Shift In — switch back to G0
0x18	CAN	Cancel — abort an in-progress sequence
0x1A	SUB	Substitute — same as CAN
0x1B	ESC	Escape — introduces all multi-byte sequences
0x7F	DEL	Delete — ignored on input by most terminals

Fe class — two-byte introducers

Sequences with ESC followed by a byte in 0x40–0x5F. These introduce richer protocols:

Sequence	Class	Introduces
ESC D	IND	Index (single-step move down)
ESC E	NEL	Next Line
ESC M	RI	Reverse Index
ESC P	DCS	Device Control String (used by Kitty graphics, tmux passthrough)
ESC [	CSI	Control Sequence Introducer — see CSI
ESC \	ST	String Terminator
ESC ]	OSC	Operating System Command — see OSC
ESC ^	PM	Privacy Message
ESC _	APC	Application Program Command (used by Kitty graphics)

See also

• VT Overview
• Sequence Reference — full table.