Orbit, Pan, Zoom, Dimensions, Protractor
Orbit - "O" Key, or hold down scroll wheel of your mouse
This tool changes the camera angle.
Pan - "H" Key
This tool moves the camera up and down or side-to-side.
Zoom - "Z" Key
Dimensions - No shortcut key
Take measurements of an object.
Protractor - No shortcut key
Take angled measurements of an object.
VCB - Value Control Box contains dimensions or measurements of lines and faces. It shows you the measurement of a line as you click from point A to point B. Or you can type in the exact measurement directly.
ESC key - On your keyboard, select this key whenever you have completed a line or to quickly exit out of the tape measure and rotate tools.
CTRL + Z - Undo. You'll need this a lot!