Superman has the ability to naturally defy and operate independently of gravity and propel himself through the air at will.

Originally, he only had the power to jump great distances. He could leap over an 8th of a mile or over a tall building, in a single bound. Later on he learned how to fly, first by maneuvering in mid-air and later on by completely countering gravity. He is able to accelerate, float in midair, and change direction while traveling.