Why do all the Aeroplane almost have the same design?

When you look at planes in the sky, you may notice that they pretty much look the same except for the paint. There are no major changes to the design of each plane even if the planes were owned by different airlines and were made by different manufacturers. The main reason has to do with having the ability to fly. Actually, flights are really still in the beginning stages compared to other modes of transportation.

In order to fly and use less fuel, the layout of the plane is similar. Also, no other inventions have been created to alter the design of the airplane that would make it fly safer, faster, better or cheaper. Therefore, the airlines must stick with the original layout and design that has been around for many years.