电脑键盘上，“退出键”指的是一个标有“Esc”或“Escape”的按键，它用于生成ASCII换码字符（控制键-[，十进制中ASCII代码27），传统上，这个字符代码被用来产生换码顺序。

由于后来大多数计算机用户不再需要介入对计算机周边设备控制时的细节操作，这个换码顺序原先被设计要运行的任务，退出键开始转而被应用软件设计员利用，并最常被用于表示“中止”。这一用法沿用至今日，退出键成为许多网页浏览器中“停止”按钮的通用快捷键。此外，微软Windows当中，它还成为对话框中表示“否”、“退出”、“取消”、“放弃”的快捷键。

On computer keyboards, the Esc key (named Escape key in the international standard series ISO/IEC 9995) is a key used to generate the Escape character (which can be represented as ASCII code 27 in decimal, Unicode U+001B, or Ctrl+[). The escape character, when sent from the keyboard to a computer, often is interpreted by software as "stop", and when sent from the computer to an external device (including many printers since the 1980's, computer terminals and Linux consoles, for example) marks the beginning of an escape sequence to specify operating modes or characteristics generally.