[X]

Via 3-Button Mouse:

Rotation

Hold down left mouse button and drag mouse.

Zoom

Hold down middle mouse button and drag. Do not scroll the wheel. Simply push down on the wheel and drag.

Pan

Hold down right mouse button and drag mouse.

Via Mouse & Keyboard:

Rotation

Hold down "A" and move mouse.

Zoom

Hold down "S" and move mouse.

Pan

Hold down "D" and move mouse.