What Does Escape Key (ESC) Mean?
The escape key (ESC) on a keyboard is a specific standardized part of the programming characters routinely accepted by a computing system through the keyboard peripheral. It represents code 27 in the ASCII character set, and can be substituted by the control plus left bracket (CTRL + [) hot-key combination.
Techopedia Explains Escape Key (ESC)
In the beginnings of computing, the escape key was a way to move from one computing task to another. In more modern setups, the major use of the escape key is to allow end users to access a particular application without using specific menu commands.
Like other function keys such as print screen, the escape key is something that has become intuitively familiar to general users who aren't familiar with programming principles. With that in mind, each software interface has its own rules, and some of the less user-friendly software may suffer from design flaws where uneducated users try to exit unsuccessfully with the escape key.