Oncomputer keyboards, theEsc keyEsc (namedEscape key in the international standard seriesISO/IEC 9995) is a key used to generate theescape character (which can be represented asASCII code 27 in decimal,Unicode U+001B, orCtrl+[). The escape character, when sent from the keyboard to a computer, often is interpreted by software as "stop", "cancel" or "exit", and when sent from the computer to an external device (including many printers since the 1980s,computer terminals andLinux consoles, for example) marks the beginning of anescape sequence to specify operating modes or characteristics generally.
It is now generally placed at the top left corner of the keyboard, a convention dating at least to the originalIBM PC keyboard, though the key itself originated decades earlier withteletypewriters.
The keyboard symbol for the ESC key (which may be used when the usual Latin lettering is not preferred for labelling the key) is standardized inISO/IEC 9995-7 as symbol 29, and in ISO 7000"Graphical symbols for use on equipment" as symbol ISO-7000-2029. This symbol is encoded inUnicode as U+238Bbroken circle with northwest arrow (⎋).
The name of the equivalent key on some earlyTeletype Model 33 keyboards was labeledAlt Mode..., the alternative mode of operation causing the escapement to treat the following one character in a special way. Much later printers andcomputer terminals that would useescape sequences often would take more than one following byte as part of a special sequence.
As most modern computer users are no longer concerned with controllingterminal orperipheral behaviour via manually typed or computer-issued escape sequences, the task to whichEsc was originally dedicated, the escape key has long since been appropriated byapplication programmers, most often to meanStop. This use continues today inMicrosoft Windows's method of escape as a shortcut in dialog boxes forNo,Quit,Exit,Cancel, orAbort, as well as a common shortcut key for theStop button in manyweb browsers, and to canceldrag and drop operations.[1][2][3]
On machines runningMicrosoft Windows, prior to the implementation of theWindows key on keyboards, the typical practice for invoking the "start" button was to hold down theControl key and press escape. This key combination still works as of Windows 11.[4]
Microsoft Windows makes use of "Esc" for many key shortcuts.[5] Many of these shortcuts have been present sinceWindows 3.0, throughWindows XP and later.
In macOS, "Esc" usually closes or cancels a dialog box or sheet. The⌘ Command+⌥ Option+⎋ Esc combination opens theForce Quit dialog box, allowing users to end non-responsive applications. Another use for the Esc key, in combination with the Command key, is switching toFront Row, if installed.
In most computer games, the escape key is used as a pause button and/or as a way to bring up the in-game menu, usually containing ways to exit the program. This is despite the existence of a separatePause/Break key.
In thevi family of text editors, escape is used to switch modes. This usage is a legacy of theEsc key being conveniently placed in thetop row on theADM-3A terminal keyboard used to develop vi, in what on modern keyboards is now the tab position – yet on modern keyboards, Esc is now inconveniently located, most often in thefunction keys row. This is similar to how the extensive modifier keys inEmacs were easily used on the original keyboard (thespace-cadet keyboard)—being placed together—but these keys have now been spread around the keyboard, and hence become more difficult to use.
TheTECO editor uses ESCape as a delimiter when used once, and as anexecute key when used twice in a row.[6]
Old keyboard Send/Receive (KSR) printers, andvisual display units (VDUs), would normally be controlled byescape sequences sent by the computer to the peripheral device, but there were situations where these devices could be used "off-line" with the keyboard effectively connected to the output device, and so the need could arise to type escape sequences "by hand" to control the peripheral. Although such devices are long out of use, standard processing[7] ofANSI Escape sequences very similar to the 1970sVT100, is implemented in bothANSI.SYS and other more modern pseudo-terminal interfaces used inUnix-like environments, one example beingLinux consoles, meaning newer, higher-level abstractions haven't changed the fact that typing the escape key followed by something like the six characters[32;1m affects subsequently text in output, in this case turning it green.
| Esc | F1 | F2 | F3 | F4 | F5 | F6 | F7 | F8 | F9 | F10 | F11 | F12 | PrtScn/ SysRq | Scroll Lock | Pause/ Break | |||||||||
 | Insert | Home | PgUp | Num Lock | ∕ | ∗ | − | |||||||||||||||||
| Delete | End | PgDn | 7 | 8 | 9 | + | ||||||||||||||||||
| 4 | 5 | 6 | ||||||||||||||||||||||
| ↑ | 1 | 2 | 3 | Enter | ||||||||||||||||||||
| ← | ↓ | → | 0 Ins | . Del | ||||||||||||||||||||