keyboard (blue) of course represents the built-in single octave keyboard, a wonderful asset for demoing sounds or quick composition on the go. You can override these if you wish when your needs require it, but I prefer to leave it alone.

system (red) represents unmappable keys that are used as modifiers & computer-related input.

ableton (yellow) are the keys that already have function in live without modifiers, including z & x (keyboard octave change), c & v (keyboard velocity change), & tab (switch between arrangement & session views).

Keep in mind that Live distinguishes between capitals, so if you want to map some of these default shortcuts without overriding their functions, you can. For example, b enters draw mode, but you could map B to turn the metronome on & still preserve the lowercase b for draw mode.