A projectile is any object you throw, hit or fling. Bowling balls, tennis balls, golf balls, and ping pong balls are all spheres which always bounce the same way. A hockey puck is a cylinder which glides on the ice. A football is a prolated spheroid which moves efficiently through air with its pointed ends. A baseball is a sphere which forms a parabolic arc in the air when thrown. A Frisbee is a circular wing, and like an airplane, creates lift when it is projected. A badminton birdie is shaped like a cone and its feathers slow it down and act like a parachute. And a soccer ball is made up of pentagons and hexagons forming its surface - a truncated icosahedron. The stitches on the surface of a baseball can be used by a pitcher to throw curve ball, sliders, and screwballs. Gravity pulls projectiles back to the ground and drag slows them down. Each sport has a different shaped projectile.