What are the signs of a bad starter on a Chevy S10?

1. engine won't start. 2. All you get is a click when you turn the key. (make sure that you have a good battery) 3. You hear a whirring sound but the engine does not crank. (the starter motor turns but the bendix does not engauge. 4. You hear this gosh awful screaming sound. (the starter spins but does not engauge the flywheel completely.) Probably a lot more but these have happened to me over the years. You can take the starter off (if you are mechanically inclined) and some auto parts stores will test them for you. Auto Zone does where I live.