More After Effects Keyboard shortcuts

There are many shortcut keys for you to use in the layers of After Effects. Your keys for using layers are very important and save many steps with a mouse based workflow. There are many more shortcuts than the ones listed here but I feel that these are the most useful shortcuts to remember. Put these shortcuts to practice and save yourself many clicks with your mouse.
1. Enter key on main keyboard Rename layer, composition, folder, or effect
2. Ctrl + Down Arrow key Select next layer back
3. Ctrl + Up Arrow key Select next layer forward
4. 1 - 9 on numeric keyboard Select a layer by its layer-outline number
5. Ctrl-click layers Select non-contiguous layers
6. F2 Deselect all layers
7. Enter on numeric keypad Display selected layer in Layer window
8. Alt-double-click a layer Open source of a layer
9. Ctrl + Alt + R Reverse a layer's playback
10. [ (left bracket) Set In point
11. ] (right bracket) Set Out point
12. Alt + [ (left bracket) Trim In point of a layer
13. Alt + ] (right bracket) Trim Out point of a layer
14. Alt-click a property stopwatch in the Effect Controls window Add/remove expression
15. Alt + Home Move In point to beginning of composition
16. Alt + End Move Out point to end of composition
I know this seems like a lot of shortcuts to remeber but I thinks once you put them into practice you will never forget.

