How to identify NPN & PNP transistor?

1. Turn your multi-meter knob towards ‘diode’ mark, where we do short-circuit test.
   
2. Put Red color lead at Base of transistor and black at either side.
   
   If there is any deflection, then the transistor you are tested, that is N-P-N transistor.
   
3. Put Black color lead at Base of transistor and Red at either side.
   
   If there is any deflection, then the transistor you are tested, that is P-N-P transistor.