What is the difference between a Chef and a Major?

The main difference between the two machines is the size.

The Major has a 7 Quarts bowl and the Chef a 5 Quarts bowl.

The motor size will also be different for a Major (800 Watts) for a Chef (750 Watts).

It is worth noting that the Major is a taller and heavier machine as it can mix larger quantities at one time.