What is a recumbent?
The word recumbent refers to the seated position. On a recumbent bike you sit in a chair-shaped seat (reclined position) and the pedals are out in front of you. This is actually a more ergonomic way to design a bicycle. Recumbents have better pedaling efficiency, much better comfort for extended riding, and better aerodynamics even without fairings. Recumbent riders sometimes refer to conventional "upright" bicycles as "wedgie bikes or DF’s (diamond frame)". Recumbents have been around for more than a hundred years.
Why aren’t there more of them? In 1933, a Frenchman by the name of Marcel Berthet rewrote a number of cycling records beating professional bike riders of the time on a recumbent. The French Union Cycliste Internationale (UCI) decided in 1934 to ban them from competition as they were just of such a superior bike design.