Craters are bowl-shaped depressions found on the surface of planets, moons, and other celestial bodies. They are primarily formed by the impact of meteoroids, asteroids, or comets colliding with the surface at high speeds. The force of the impact creates a cavity, often surrounded by a raised rim of debris. Craters can vary in size, from small pits to large basins, such as the Tycho crater on the Moon. Some craters may also show signs of erosion or volcanic activity, which can alter their appearance over time. Studying craters helps scientists understand the history and geology of these celestial bodies.