Projectile motion refers to the motion of an object that is thrown or projected into the air, influenced only by the force of gravity and air resistance. This type of motion follows a curved path known as a trajectory, which is typically a parabola. The object moves horizontally and vertically at the same time, with its horizontal motion being constant and its vertical motion accelerating downward due to gravity. The key factors affecting projectile motion include the initial speed, launch angle, and height of the object. The angle at which the object is launched determines how far it will travel horizontally and how high it will go. Understanding these principles is essential in fields like sports, engineering, and physics.