Stellar abundances refer to the quantities of different chemical elements found in stars. These elements are produced through nuclear fusion processes within stars and can vary significantly depending on the star's age, mass, and evolutionary stage. By studying the light emitted from stars, astronomers can determine the composition of these elements, which helps us understand the formation and evolution of the universe. The study of stellar abundances is crucial for understanding the lifecycle of stars and the chemical enrichment of galaxies. Elements like hydrogen, helium, and heavier elements such as carbon and iron are key to this research. This information also aids in the study of supernovae and the distribution of elements in the cosmos.