The MG996R is a metal gear servo motor with a maximum stall torque of 11 kg/cm. Like other RC servos the motor rotates from 0 to 180 degree based on the duty cycle of the PWM wave supplied to its signal pin.
2212 (BLDC) BRUSHLESS DC MOTOR is a high speed brushless motor designed specifically for Quadcopters, Drones or toy planes. The motor is OUTRUNNER type where outside case rotates while inside stays fixed. It is one of popular model in the market because it’s low cost.