The Solar System consists of the Sun and everything that orbits it, including 8 planets, Pluto, moons, asteroids, comets and other objects. The 4 inner planets are small and rocky, while the 4 outer planets are large gas giants. The document describes each planet's characteristics such as composition, size, orbital period, moons, temperature and other features. It explains that the Sun is at the center and provides energy through nuclear fusion, while planets reflect sunlight.