Stars are massive, glowing balls of gas that produce light and heat through nuclear fusion. They are primarily made up of hydrogen and helium and can be found in various sizes and colors. The closest star to Earth is the Sun, which provides the energy necessary for life on our planet. In the night sky, we can see countless stars, many of which are part of constellations. These patterns help us navigate and tell stories from different cultures. Stars are also important for understanding the universe, as they can reveal information about its age and the formation of galaxies.