To many, aircraft all look the same. It is a hollow metal cylinder with a tail and two wings on either side. There are those however who view aircraft just like they do cars. Engines are a hot topic in the world of mechanics. Depending on the engine, a machine can speed around a racecourse, take off into the sky, or slowly get you from point A to point B. Aircraft are defined in terms of their engines, with the three main types including turbojet engine, turbofan engine and turboprop engine. Before going into detail about the pros and cons of each of these engine types, we should know where they began. Dr. Hans Van Ohain and Frank Whittle are recognized as the co-inventors of the jet engine. The inventors believed that there was a better way to power an aircraft than a piston-based engine. After all, the hardest part is over - aircraft were already in the sky. It was in 1939 that the first jet engine took flight. Now we can look into the different types of engines.