An induction electric motor or 3 stage induction motor is an AC electric engine in which the electric current in the rotor needed to generate torque is obtained by electromagnetic induction from the magnetic field of the stator winding
An induction electric motor which connects with a 3-phase supply called 3-stage induction motor. Example supporters,Three Phase Motor blowers, cranes,traction .It is a ac electric motor. The primary drawback of DC motors may be the presence of commutator and brushes, which require frequent maintenance and we can not use DC motor in explosive and dirty environment. But induction 
motors are cheaper,tough,lighter,smaller,require less maintenance and will use in dirty and explosive environment. Slide s is the imp element in this kind of motor.
There are 2 types of IM.
Squirrel cage IM
Slip ring IM
There are many 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 reverse voltage braking
Dynamic braking
But one thing swiftness control technique of induction motor is important
Pole changing
Stator voltage control
V/f control
Slip power recovery
Rotor resistance control