Classical physics (or classical mechanics) is a group of physics theories that predate modern, more complete, and more widely applicable theories associated with quantum physics (quantum mechanics).
Classical physics describes many aspects of nature at an everyday scale but neglects to explain things at very small (sub-atomic) and very large (cosmological) scales. It is a very successful theory, and many of its predictions have been experimentally verified.
Classical physics studies the motion of macroscopic objects, from projectiles to parts of machinery and astronomical objects such as spacecraft to the movement of planets and stars.
For objects governed by classical physics, if the present state is known, it is possible to predict how it will move in the future (determinism), and how it has moved in the past (reversibility).