What is the difference between motor and generator in electrical machine?

A motor converts electrical energy into mechanical energy and a generator converts mechanical energy into electrical energy.

Longer answer

The primary difference between a motor and a generator is that one converts electrical energy into mechanical energy (that's the motor) and the other converts mechanical energy into electrical energy (that's the generator).

In some cases of direct current (DC) machines, but not alternating current (AC) machines, there is so little difference that a single device (it might be called a motor-generator) can be used as either a motor or a generator.

A superb example of this would be the motor-generator that is used in electric vehicles: when the vehicle is accelerated, the batteries supply power to the motor-generator and it acts as a motor, driving the wheels. When the brake is applied, the motor-generator shifts function and the vehicle's inertia is used by the motor-generator to generate electricity and put some energy back into the batteries. This slows the vehicle down. The one device (the motor-generator) is being used in either capacity. The "handle" often applied to electric vehicles with this feature is dynamic braking.
They alike because they both have stators and rotors they are different in that the generator is driven by mechanical device that rotates the rotor, the rotor cuts through magnetic force fields and electricity is generated. The motor is driven by an input of electricity into the stator and the rotor is forced to turn by reaction with magnetic force fields.
Generator will provides current to load ......... but motor will drawn current............... generator is based on Flemming right hand rule but motor is based on left hand rule.