Relativity means the laws of physics are the same everywhere. What laws of light and gravity we observe are the same for someone in a far off corner of the universe.The same applies to time.time and space are relative. Time passes slower the faster one goes. If a twin rides in the speeding spaceship to some distant star and then comes back she will be younger than her sister who stayed on Earth.Different viewers will see the timing and spacing of events differently. What for us are a million years may just be a blink of an eye for someone flying in a high-speed rocket or falling into a black hole.