Input buffering
Storing a button press for a short while so the action still fires even if it was pressed slightly too early.
If the player presses jump a frame before the character lands, most games want to jump right at touchdown rather than swallow the press. Input buffering solves it by putting each command in a small queue with a timestamp; once the state does allow the action, the most recent buffered press within the window is pulled out.
Fighting games pushed the technique furthest — there, whole command sequences are buffered so a special move can be entered just before the previous animation ends, which is what makes links and combos possible. In platformers it is the twin of coyote time: one forgives a jump that came too late, the other one that came too early. Both buffer windows are kept short so the controls feel tight rather than mushy.