What is an electric motor

  This conversion is usually obtained through the generation of a magnetic field by means of a current flowing into one or more coils.

Rotor and stator magnetic fields

The rotation is obtained thanks to the attractive force between two magnetic fields:
  One field is located on the rotor (the moving part).
  The second magnetic field is located on the stator (the body of the motor).

Usually one of the two is generated by a permanent magnet while the other one is generated through an electromagnet (solenoid).