Did you know that the ALT Key is a context sensitive command in Photoshop and has dozens (maybe more) of functions? It all depends on what you are doing in photoshop, and the maddening thing about all this is that I don’t think there is a list of everything this little guy does. Its like a Photoshop scavenger hunt.

For example:

-Hold the ALT key down when making a layer mask, do you notice anything different?
-Hold the ALT key down when clicking “cancel” on any dialog box- do you see what it changes to?
-Hold the ALT key down when adjusting Sharpness in RAW (but you must be in 100% to see it)
-Hold the ALT key down when moving a selection.
-Hold the ALT key down when using undo to step back multiple steps.
-Hold the ALT Key down when wanting to apply the same adjustments as last time.

I dont understand why Adobe would have all these hidden shortcuts and not have them written down somewhere.