Using the tools

Result	Windows Action	Macintosh Action
Crop tool	C	C
Drag selection tool (Composition window only)	U	U
Ellipse tool	L	L
Eyedropper tool	I	I
Eyedropper tool samples style	Shift + click	Shift + click
Hand tool	H	H
Layer offset tool	O	O
Paint bucket tool	K	K
Paint bucket tool applies last style sampled by eyedropper tool	Shift + click	Shift + click
Pen tool (Composition window only)	P	P
Pen select tool (Composition window only)	S	S
Polygon tool	N	N
Preview mode	Q	Q
Rectangle tool	M	M
Rounded-rectangle tool (Composition window only)	R	R
Selection tool	V	V
Subgroup selection tool (Composition window only)	A	A
Text field tool	Y	Y
Transform tool	E	E
Type tool (Composition window only)	T	T
Zoom tool	Z	Z
Switches to zoom out tool	Alt + Z	Option + Z

Note: Tapping a key will permanently switch to a tool. Holding a key will temporarily switch to a tool until the key is released.