An Three Phase Motor induction electric motor or 3 phase induction motor can be an AC electric motor in which the electric energy in the rotor needed to generate torque is obtained by electromagnetic induction from the magnetic field of the stator winding
An induction motor which connects with a 3-stage supply called 3-phase induction motor. Example fans,blowers, cranes,traction .It is a ac motor. The primary drawback of DC motors may be the existence of commutator and brushes, which require regular maintenance and we can not use DC engine in explosive and filthy environment. But induction motors are cheaper,tough,lighter,smaller,require less maintenance and may use in dirty and explosive environment. Slide s may be the imp aspect in this kind of motor.
There are 2 types of IM.
Squirrel cage IM
Slip ring IM
There are various 
starting and braking condition.
Important starting methods are
Star-delta starter
Auto transformer starter
Ac voltage controller starter
Rotor resistance starter
Important braking methods are
Regenerative braking
Plugging or invert voltage braking
Dynamic braking
But one thing rate control technique of induction motor is important
Pole changing
Stator voltage control
V/f control
Slip power recovery
Rotor resistance control