Who gave the theory of relativity?

 The theory of relativity is a set of two theories of physics developed by Albert Einstein: the special theory of relativity and the general theory of relativity.

The special theory of relativity, which was published by Einstein in 1905, is a theory of space and time that describes the fundamental principles of motion at constant speeds in a vacuum. The theory of relativity was developed in response to problems with the classical Newtonian theory of motion and introduced the concept of time dilation, which states that time appears to pass at different rates depending on the relative speed of the observer.

The general theory of relativity, which was published by Einstein in 1915, is an extension of the special theory of relativity that describes the fundamental principles of motion at all speeds, including those near the speed of light. The general theory of relativity introduced the concept of gravity as a curvature of spacetime caused by the presence of mass or energy.

Overall, the theory of relativity is a revolutionary set of theories that changed our understanding of space, time, and motion and had a major impact on the development of modern physics.