Permanent magnetMakes the magnetic field the coil turns in. In a small motor the magnets are the stator, the part that stays still.
Coil (windings)Wire carrying current in the magnetic field. The push on it turns the rotor.
ShaftThe rod that turns with the rotor and delivers the motor's work.
CommutatorA split ring on the shaft. It reverses the current in the coil every half turn, so the coil keeps turning the same way.
BrushesCarbon blocks that rub on the commutator. They carry current into the spinning coil.
Rotor (armature)The part that spins, an iron core carrying the windings.
Other 2
TerminalsWhere the power supply connects to the motor.
Casing (housing)The case that holds the motor together. In a small motor it also carries the magnets.
How this list was compiled: Read 2026-09-26. (1) The Engineering Mindset, DC motor explained, https://theengineeringmindset.com/dc-motor-explained/ : the stator of permanent magnets, the rotor or armature with its coil windings, the shaft, the commutator and brushes, the casing, the terminals. (2) Wikipedia, Electric motor, https://en.wikipedia.org/wiki/Electric_motor : stator and rotor, armature, windings, permanent magnets, commutator and brushes, shaft, bearings, housing. (3) OpenStax Physics, 20.2 Motors, Generators, and Transformers, https://openstax.org/books/physics/pages/20-2-motors-generators-and-transformers : a current loop on a shaft in a magnetic field; brushes reverse the current so the torque keeps the same direction. Licence: own work
The drawing: Drawn for this site by script, 2026-09-26. Own work, nothing traced. Licence: own work
How it works
These are the parts of an electric motor, first as a simple DC motor the way textbooks draw it, then a real small motor cut across. The magnet and coil rings light up in both.
Read the full guide
How it turns
Current comes in at the terminals and through the brushes to the commutator and the coil. The magnets' field pushes on the current-carrying coil, turning it and the shaft.
Why it keeps turning
Every half turn, the split-ring commutator swaps which brush feeds which end of the coil, reversing the current, so the push keeps turning the coil the same way.
In a real motor the coil is wound round the arms of an iron rotor, and the magnets sit in the casing: the stator.
Questions and answers
What is the difference between the stator and the rotor?
The stator is the part that stays still, in a small DC motor the permanent magnets in the casing. The rotor, or armature, is the part that spins, with the windings and the shaft.
What does the commutator do in a motor?
It is a split ring on the shaft. As the coil turns, it reverses the current in the coil every half turn, so the coil keeps turning in one direction.
What are brushes in an electric motor?
Blocks, usually of carbon, that press on the commutator and carry current into the spinning coil. They wear down over time.