A compose key (sometimes called multi key) is a key on a computer keyboard that indicates that the following (usually 2 or more) keystrokes trigger the insertion of an alternate character, typically a precomposed character or a symbol.
It’s a method to combine several characters on your keyboard and use it to create a special character which is not on the keyboard. For example “ and e produces ë. This tool allows you to configure those combinations.
But thanks for the feedback. I’ll update the readme to add some more context.