A graviton is a theoretical elementary particle that mediates the force of gravity in quantum field theory. It is proposed to be massless and travel at the speed of light, similar to how photons carry the electromagnetic force. Gravitons are part of the framework that attempts to unify quantum mechanics and general relativity, although they have not yet been observed. In the context of physics, the existence of gravitons is suggested by the need for a quantum explanation of gravity, which is traditionally described by Albert Einstein's theory of general relativity. While many particles have been detected, the graviton remains hypothetical, and its discovery would significantly advance our understanding of the universe.