An induction engine or asynchronous motor can be an AC electric engine in which the electric current in the rotor had a need to generate torque is obtained by electromagnetic induction from the magnetic field of the stator winding. … An induction motor’s rotor can be either wound type or squirrel-cage type.
Benefits of AC Induction Motors are:

Induction motors are simple and rugged in building. They are better quality and can operate in any environmental condition
Induction motors are cheaper in cost due to simple rotor construction, lack of brushes, commutators, and slide rings
They are maintenance free motors unlike dc motors due to the lack of brushes, commutators and slip rings
Induction motors could be operated in polluted and explosive environments as they do not have brushes which can cause sparks
AC Induction motors are Asynchronous Devices and therefore the rotor will not switch at the specific same speed because the stator’s rotating magnetic field. Some difference in the rotor and stator swiftness is necessary to be able to create the induction in to the rotor. The difference between your two is named the slip. Slip should be kept in a optimal range to ensure that the motor to operate effectively. Roboteq AC Induction controllers can be configured to operate in one of three modes:

Scallar (or Volts per Hertz): an Open up loop mode in which a command causes a simultaneous, fixed-ratio Frequency and Voltage alter.
Controlled Slip: a Shut Loop speed where voltage and frequency are managed in order to keep slip inside a narrow range while working at a preferred speed.
Field Oriented Control (Vector Drive): a ac motor Closed Loop Acceleration and Torque control that works by optimizing the rotating field of the stator vs. this of the induced field in the rotor.
Observe this video from Learning Engineering for a visual illustration about how AC Induction Motors are constructed and work.