Some actions in Spelunky can be performed by pressing a single key, instead of pressing many. For example, to throw a bomb, usually the player must first switch to it with the C key, then press X once to light it, and again to throw it. Pressing the A key does all of these.
Key List Edit
|A||Throw a bomb in the direction you are facing or holding on the keyboard (i.e, pressing up will throw the bomb at a higher trajectory, just like normal.)|
|S||Throw a rope (in the same way as you normally use a rope, so holding down near an edge and pressing S will unfurl the rope so you can climb down).|
|F4||Toggle between fullscreen and window mode.|
|F10||Quit the game.|
|Esc then F1||Kill yourself.|