The most commonly used motors are DC motors, which spin to generate electricity, but because these are imprecise, another kind of motor has to be used in machines that require a great degree of precision. Since stepper motors are specifically designed for accuracy, you will find stepper motors in some of the most commonly used pieces of computer equipment. In the hard and floppy disk drives, for example, a stepper motor moves the read or write head over the surface of your disk so you can read or transfer contents from your disk to your computer and vice versa. A stepper motor also moves the paper being fed into your printer. Stepper motors are not to be confused with servo motors, which are the motors mainly in use in robotics for radio controlled airplanes, cars, and puppets.
Stepper motors come in different types and designs, with varying resolutions and winding schemes. The type of stepper motor that is used depends on the level of precision needed by the device that the stepper motor is attached to. CNC, or Computer Numerical Controlled machines, like a system for creating component designs, would require a greater degree of precision. This means that the motor should be stronger than normal and should be able to generate more steps per rotation.
Stepper motors are understandably a bit more complicated than DC motors. DC motors have two wires, but stepper motors might have as many as six or eight. Therefore they need a special electronic device to make sure that they will work properly. This is the stepper motor drive, which has a motor driver circuit and motor wiring that allows it to convert bits of information so that the right amount of electricity flows into the right wires at the proper time. The main point of these drivers is to make sure that the electricity in the stepper motor is being properly directed to where it is supposed to go. Concerning electrical connectors for wiring devices, NEMA connectors are the most in use in North America and Canada, and are therefore largely available. The NEMA 2 series, however, has been rendered obsolete and is no longer available in the market.
Stepper motor drivers up for purchase are easily available online at sites like Mouser and Interinar Electronics. Mouser is a worldwide electronics company operating online and has many different types of drivers available in their store from their various suppliers. Interinar have drivers for bipolar and unipolar motors whose prices you can easily compare with those of other drivers available online, and with the option to view a comprehensive product description. If you're looking for cheap stepper motor drivers, you can look at smaller sites like SparkFun and taomc.com, or visit Shopping.com or Alibaba.com for any good offer they might have running.
You can also check for other special resources in the Net for tutorials on how to set up a stepper motor and stepper motor driver in your computer, or how a hobbyist might be able to use it for toys with complicated robotics.