The Sun is classified as a star, specifically a G-type main-sequence star (G dwarf). It is located at the center of our solar system and is the closest star to Earth, providing the light and warmth necessary for life. The Sun is primarily composed of hydrogen and helium, undergoing nuclear fusion in its core, which produces energy that radiates into space. This process generates light and heat that supports photosynthesis in plants and regulates Earth's climate. The Sun’s immense gravity also keeps the planets, moons, and other celestial bodies in orbit around it.