The quadcopter is one of the top-selling products in the world of remote-controlled vehicles – so many people are already using them. A quadcopter is an unmanned helicopter that has a total of four rotors. It has a total of four arms – each arm has a propeller and a motor at the end of it. In some ways, they are similar to helicopters. However, the difference is – their lift and thrust come from four different propellers, instead of one.