Understanding Stepper Motors
“A stepper motor is a brushless, synchronous electric motor that can divide a full rotation into a large number of steps. When commutated electronically, the motor’s position can be controlled precisely, without any feedback mechanism” (citation from Wikipedia) Any DIY Maker should understand the workings of stepper motors, Ask any Robot maker, just about any motion control a robot makes is done with stepper motors. Here are a few links