Brushed motors are the easiest type of motor to control and setup. As they work using a split ring commutator, the current is automatically changing direction on the coils as the motor spins around.

These motors only require two wires (+) and (-) and are much simpler to control the speed of. The basic function of an electronic speed control is to switch the supply voltage ON and OFF at different rates, if the motor only needs to turn slowly the ON signal will be given for a shorter amount of time than the OFF signal. This output signal is one of the reasons why you can hear a buzz on low throttle before the motor starts turning.

Brushed motors have the coil as part of the rotating armature so the commutators can change the direction of current as it spins around. These commutators generate an efficiency loss and are one of the reasons why brushless motors are starting to increase in popularity.

Advantages

Easy to setup and run.
Fairly cheap to buy.
They don't need any special speed controllers.


Disadvantages

Get very hot if run at high speed for any length of time.
Consume more current than brushless motors.
Fairly slow compared to brushless systems.