A quasar is an extremely bright and distant object in the universe, powered by a supermassive black hole at its center. As matter falls into the black hole, it heats up and emits vast amounts of energy, making quasars some of the most luminous objects known. They can outshine entire galaxies and are often found at the centers of galaxies. Quasars were first identified in the 1960s and are important for understanding the early universe. They help astronomers study the formation and evolution of galaxies, as well as the behavior of black holes. Their light can travel billions of years, providing insights into cosmic history and the expansion of the universe.