Stellar abundances refer to the relative amounts of different chemical elements present in a star. These abundances can provide important insights into the star's formation, evolution, and composition. Astronomers study stellar abundances by analyzing the absorption lines in a star's spectrum, which can reveal the presence of various elements such as hydrogen, helium, carbon, oxygen, and more. By comparing these abundances to theoretical models and observations of other stars, researchers can better understand the processes involved in the creation and evolution of stars. Additionally, studying stellar abundances can help scientists gain a better understanding of the chemical history and dynamics of galaxies.