The Sun is by far the most important source of energy for life on Earth. It is a star at the center of the Solar System. It is made of hot plasma and is a nearly perfect sphere. The sun has a surface temperature of about 5, 779 K. Based on its spectral class, it is a G-type main-sequence star. Roughly, the sun is middle-aged. The Sun has not changed dramatically for more than four billion years, and will remain stable for around five billion more years. It compromises 99.86% of the Solar System. The Sun contains different layers which include the Core, Radiative zone, Tachocline, Convective zone, the Photosphere, and the Atmosphere. Around 1 million Earths could fit into the Sun. Without the Sun’s heat and light, the Earth would be a lifeless ball of ice-coated rock. The Sun also warms our seas, stirs our atmosphere, generates our weather patterns, and gives energy to the plants, or producers, that provide food and oxygen for life on Earth. The Sun’s gravitational pull is what keeps the planets in place in their orbits. While the sun is not very special compared to the other billions of stars in the universe, to the Earth and the other planets in our Solar System, nothing is more important.