Stellar structure refers to the internal composition and layers of a star, which influence its formation, evolution, and eventual fate. A typical star, like our Sun, consists of several layers, 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 pulling inward and the pressure from nuclear fusion pushing outward defines a star's equilibrium. As a star ages, its structure changes, leading to different stages of evolution, such as becoming a red giant or a white dwarf.