One of the biggest problems in most modern cities is traffic congestion due to too many vehicles. In the future, flying cars may become a popular means of transport because of their benefits. Flying cars can reduce traffic congestions since they do not have to compete for space with cars. Additionally, flying cars can take a more direct route from point A to point B, so they need less fuel and time. Some flying cars run on hydrogen, a clean and environmentally-friendly fuel. However, flying cars need to meet the technical standards of both airplanes and cars; therefore, it can be quite costly to build and maintain them. Moreover, they cannot carry as many passengers as other public vehicles or planes. Furthermore, flying cars also cause a large amount of noise because they require a lot of energy to take off.