What Type of Electric Motor Do Servo's Use?

hi,
thanks for the replies, i'm well aware of a micro controller & its feedback in conjunciton with a potentiometer, making servos

What i really need are the physical details of the motors used, not the micro controller.

I've tried to crack my own motor open, but its sealed shut, i need to see what components the motors use

I also need to know what type of hardware the motor uses, capacitor etc.,

I also need to know what type of technology the motor uses

Also if possible how to build your own hardware electric motor, that is a motor not servo, i know how to build a servo, its the motor bit i need help with