a – direct selection tool
b – brush tool
c – crop tool
d – default foreground and background colors
e – eraser tool
f – Toggle screen modes
g – gradient tool
h – hand tool
i – eye dropper tool
j – spot healing brush
l – lasso tool
m – Marquee tool
o – dodge tool
p – pen tool
q – quick mask tool
r – rotate view tool
s – clone stamp
t – text tool
u – shape tool
v – move tool
w – quick selection tool
x – switch foreground and background colors
y – history brush tool
z – undo
When using the pen tool you can use the modifier keys to help create your shapes.
{Windows}
Shift key – removes points
Ctrl key – direct selection tool
Alt key – convert points tool
{Mac}
Shift key – removes points
Cmd key – direct selection tool
Opt key – convert points tool