The document discusses projectile motion, which refers to the motion of an object thrown or projected into the air at an angle, noting that the motion is determined by the object's initial velocity and gravity and follows a parabolic trajectory. It explores the independent horizontal and vertical components of a projectile's motion, with the horizontal motion at constant velocity and the vertical motion undergoing gravitational acceleration, and examines how changing the launch angle impacts the height, range, and time of the projectile's flight.