General relativity

General relativity is a set of ideas about how gravity works. In the simplest terms, it explains that the force of gravity comes from how objects like stars and planets bend the space around them. This means that the more massive an object is, the more it will bend space around it. The more space is bent, the bigger the force of gravity is. So, things like large planets and stars have a stronger gravity than smaller objects, because their mass causes more space to be bent.