What role does the massless particle predicted by string theory play in describing gravity?

In string theory, the massless particle predicted by the theory is the graviton, which serves as the fundamental carrier of the gravitational force.1

While string theory was initially developed to describe the strong force, physicists later realized that the theory naturally predicted a specific massless particle that did not correspond to any known subatomic particle. Researchers identified this particle as the graviton, a quantum particle with a spin of 2 that is required to reconcile quantum mechanics with general relativity. By incorporating this particle into its fundamental structure, string theory provides a framework where gravity is treated as a quantum interaction, potentially serving as a unified field theory that merges the laws of the large and the small.213