Stellar structure refers to the internal composition and layers of a star, which are crucial for its formation and evolution. A typical star consists of several zones, including the core, where nuclear fusion occurs, and the outer layers, such as the radiative and convective zones. These layers work together to produce energy and maintain the star's stability. The balance between gravitational forces and the pressure from nuclear fusion defines a star's structure. As a star ages, its structure changes, leading to different stages of development, such as the transition to a red giant or supernova. Understanding stellar structure helps astronomers learn about the life cycles of stars and the universe.