The Solar System is a star system that consists of the Sun and the objects that orbit it. The largest eight objects, which form a planetary system, are, in order of distance from the Sun: four terrestrial planets, named Mercury, Venus, Earth, and Mars; and four giant planets, including two gas giants, Jupiter and Saturn, and two ice giants, Uranus and Neptune. The word "solar" means "pertaining to the Sun," which is derived from the Latin word sol, meaning Sun. The Sun is the dominant gravitational member of the Solar System, and its planetary system is maintained in a relatively stable, slowly evolving state by following isolated, gravitationally bound orbits around the Sun.

The overall structure of the charted regions of the Solar System consists of the Sun, four smaller inner planets surrounded by a belt of mostly rocky asteroids, and four giant planets surrounded by the Kuiper belt of mostly icy objects. Astronomers sometimes informally divide this structure into separate regions. The inner Solar System includes the four terrestrial planets and the asteroid belt. The outer Solar System is beyond the asteroids, including the four giant planets. Since the discovery of the Kuiper belt, the outermost parts of the Solar System are considered a distinct region consisting of the objects beyond Neptune.

Our Solar System is the only one we know of that has a planet that supports life. So far, we only know of life on Earth, but scientists are looking for life on other worlds.