A solar system is a collection of celestial bodies that orbit a star. The most well-known example is the Solar System, which includes the Sun and eight planets, such as Earth, Mars, and Jupiter. These planets, along with their moons, asteroids, and comets, are held together by the star's gravitational pull. Solar systems can vary in size and composition. Some may have multiple stars, known as binary or multiple star systems, while others may contain gas giants or rocky planets. Scientists study these systems to understand the formation and evolution of planets and the potential for extraterrestrial life.