Gravity is a fundamental force that governs the behavior of matter in the universe. It is a phenomenon that results from the curvature of spacetime caused by the presence of massive objects. This curvature changes the path of any object traveling through it, causing it to follow a curved trajectory.

The theory of general relativity, developed by Albert Einstein, provides a comprehensive explanation of gravitational phenomena, including the orbit of planets around the sun, the motion of galaxies, and the bending of light around massive objects. According to this theory, gravity is not a force between two objects, but rather a result of the curvature of spacetime caused by the presence of massive objects.

Gravity has a significant impact on celestial bodies. It is responsible for the formation of galaxies and the structure of the universe. The gravitational pull of the sun keeps the planets in orbit around it, and it is also responsible for the tides on Earth. The study of gravity has led to a better understanding of the universe and the formation and evolution of stars and galaxies.