On computer keyboards , the Esc key is a key labeled Esc or Escape that is used to generate the ASCII Escape character ( Control -[ , ASCII code 27 in decimal), …the character code traditionally used to initiate an escape sequence ..
As most computer users no longer are concerned with the details of controlling their computer's peripherals , the task for which the escape sequences were originally designed, the escape key was appropriated by application programmers, most often to mean Stop . This use continues today in Microsoft Windows 's use of escape as a shortcut in dialog boxes for No , Quit , Exit , Cancel , or Abort , as well as a common shortcut key for the Stop button in many web browsers .    .
The ESC key has been backronymed by some to stand for "Extra Services Control".  ..
On machines running Microsoft Windows , prior to the implementation of the Windows key on keyboards, the typical practice for invoking the "start" button was to hold down the control key and press escape..
Microsoft Windows makes use of "Esc" for many key shortcuts.  Many of these shortcuts have been present since Windows 3.0 , through Windows XP , Windows Vista , and now Windows 7 ..
In Mac OS X, the most common use for the Esc key, used in combination with the Option (alt) key and the Command key , i.e. using the Alt-Command-Esc key combination, is to access the Force Application-Quit menu. Another use for the Esc key, in combination with the Command key , is switching to Front Row , if installed..
The key is indicated as a circle with an arrow through it (U+238B, â) as defined in ISO 9995 ..
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