The trajectory of a projectile refers to the path followed by an object that is launched into the air and moves under the influence of gravity, with no additional propulsion after the initial launch. Projectiles are objects that are subject to a projectile motion, such as a thrown ball, a fired bullet, or a launched rocket in its initial stage.

The trajectory of a projectile is typically parabolic in shape (assuming negligible air resistance) and is influenced by two main factors: the initial velocity and the launch angle. The force of gravity acts vertically downward, causing the object to accelerate downward while maintaining its horizontal velocity.