The three main areas of a machine are:

1. Point of Operation: This is the area where work is performed on the material, such as cutting, shaping, or forming.
2. Power Transmission Device: This part transmits energy to the portion of the machine performing the work, including components like pulleys, belts, gears, flywheels, and chains.
3. Operating Controls: These are the parts the operator uses to control the machine's operation, like buttons, switches, levers, and pedals.

These areas are fundamental to the function and safety considerations of machines.