Multirotor is the term generally used to refer to not just quadcopter, but also hexacopter, tricopters and any other unique machine which is designed with 4 rotors or propellers and more than 2 rotors.
During the 1907 two French brothers tried to improvise on multirotors. They were Louis and Jacques Breguet. Their rotor managed to take off, however they were unable to manage stability and crashed. Nobody decided to pursue after their dreams.
A French engineer Étienne Oehmichen in the year 1924 set the world record for flying his quadcopter a distance of 380 meters or 1881 feet. He was the very first person who could successfully manage to build the perfect quadcopter. Only because of lack of technology he could not do it precisely. Go to hair loss protocol review for more info.
During the contemporary period, the US Army thought of building their own military quadcopter, serving for military purposes. George de Bothezat was the one who designed the first drone for the military. Many attempts were made before finalizing the program to make sure that the design is a success.
There were many flaws in the early designs of the quadcopters. The early quadcopters were huge with a single main rotor with a tail rotor in order to counterbalance the torque. This design was more wasteful for which the quadcopter was unable to move freely all around. It will be best way if you go through their homepage. The engine was set in the middle with shafts and belts to hold the four wings together. Because of heavy weight, the quadcopter never managed to fly higher. By attaching a heavy load through the center of the device allowed to maintain stability of the multi rotor but not for long. A pilot was necessary to adjust the weight to regain stability. All the designs proved to be unsafe for which the idea was entirely wiped out.
It was only after inventing motors and propellers; engineers could finally design and manufacture their own drones successfully. The rise of technology gave us the opportunity to a safe and efficient quadcopters. The creation of multi rotors with the a flight computer finally made it possible to design the most perfect and safest quadcopter.