Ten most useful command keys on my computer are...
1.
Fn + F2 Kill volume when needing to talk to someone immedietly.
2.
Fn + F3 Lower Volume
3.
Fn + F4 Raise Volume
4.
Esc to exit fullscreen games and videos.
5.
Delete Break to delete words foward instead of backward
6.
Ctrl + Alt + Delete Break to open task manager to close frozen pages.
7.
Alt + F4 to close pages withour hitting the corner x.
8.
Ctrl C to copy images
9.
Alt + Tab to close tab
10.
Prt Sc to print screen for pictures.