Well start with the File menu from Reapers primary menu bar. The drop-down selector, found top-left, allows you to choose which elements youll customise. They lie beneath many default controls, including toolbar buttons, dropdown and contextual menus, and even fundamental commands like loading and saving projects. The Actions list comprises several thousand commands, each of which can be assigned to various different input triggers.

Actions already lie at the heart of your own interaction with Reaper for example, when you hit the space bar to start and stop playback of your timeline, youre triggering an Action named Transport: Playstop.