Theories of the Universe explore how everything began and how it works. One popular idea is the Big Bang Theory, which suggests that the Universe started from a tiny, hot point and has been expanding ever since. This theory helps explain the distribution of galaxies and cosmic background radiation, which are remnants of that explosive beginning. Another interesting concept is the Multiverse Theory, which proposes that our Universe is just one of many, each with its own unique properties. This idea raises questions about the nature of reality and whether other universes could support different forms of life or even different laws of physics.