cheat sheets.

= SAVING

Cmd-Shift-3 - Take picture of the entire screen
Cmd-Shift-4 - Take picture of selected area
            - Hold Spacebar to move selected area (whilst dragging)
            - Hold Shift to change size in one direction only
            - Hold Option for centre-based resizing
            - Press Spacebar and click window for just that window

= COPYING

To copy images to the clipboard use the keystrokes above, but include Ctrl.