The Sun is composed of several distinct layers, each with its own characteristics and functions. The innermost layer is the core, where nuclear fusion occurs, producing the Sun's energy. Surrounding the core is the radiative zone, where energy is transferred outward through radiation, taking a long time to move through this dense region. Above the radiative zone is the convective zone, where energy is transported by convection currents; hot plasma rises to the surface, cools, and then sinks back down to be reheated. The visible surface of the Sun is called the photosphere, which emits the sunlight we see. Above the photosphere lies the chromosphere, a thin layer that can be observed during solar eclipses, and the outermost layer is the corona, which extends millions of kilometers into space and is visible during total solar eclipses. The corona is much hotter than the surface and is still a subject of scientific research to understand its heating mechanisms.