When the 1967 Mazda Cosmo sports car hit the market, it was considered one of the most futuristic and cutting-edge models on offer at the time. This was chiefly due to its use of a Wankel engine, also known as a rotary engine. Instead of a conventional motor that uses pistons housed in cylinders to provide power, a rotary engine uses a spinning, triangular-shaped “piston” to produce its oomph.