Escape sequence

An escape sequence is a series of characters used to change the state of computers and their attached peripheral devices. These are also known as control sequences, reflecting their use in device control. Some control sequences are special characters that always have the same meaning. Escape sequences use an escape character to change the meaning of the characters which follow it, meaning that the characters can be interpreted as a command to be executed rather than as data.

Escape sequences are commonly used when a computer and a peripheral have only a single channel through which to send information back and forth. If the device in question is "dumb" and can only do one thing with the information being sent to it (for instance, print it) then there is no need for an escape sequence. However most devices have more than one capability, and thus need some way to distinguish information that is to be treated as data from information that is to be treated as commands.

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