This is a short tutorial on how a servo works at an electrical level. The position of a servo is determined by the pulse, which is normally between 1ms and 2ms. However, many servos have different ranges that can even be 0.5ms and 2.5ms. The EZ-B supports a wide range by providing 0.5ms to 2.5ms.
The pulses are looped every 20ms (which means 5 pulses per second)