It has many of the same parts as an airplane except for its engine configurations. The orbiter has wings that create lift. An elevon is a combination of an elevator and an aileron. On most airplanes, the elevator is located on the horizontal stabilizer as part of the tail section. The ailerons are found on most airplanes at the trailing edge of each wing.
Ailerons control an airplane's roll motion.
Because of the orbiter's delta wing configuration, the elevators and ailerons are combined as elevons and placed at the trailing edge of each wing. It does this by splitting in half vertically and opening like a book. This deflects the airflow, increases drag and decreases the orbiter's speed as it rolls along the runway upon landing. The airplane-like control surfaces on the orbiter are useless in the vacuum of space. However, once the orbiter re-enters the earth's atmosphere, these control surfaces interact with the air molecules and their airflow to control the orbiter's flight path.