Protoplanetary disks are flat, rotating circumstellar disks of dense gas and dust found around young stars. These disks are the birthplace of planets and other celestial bodies in the process of forming solar systems. They are typically composed of gas, dust, and ice particles, and can range in size from a few astronomical units (AU) to several hundred AU in diameter. Protoplanetary disks play a crucial role in the formation and evolution of planetary systems, as they provide the material from which planets, moons, asteroids, and comets are formed. Studying protoplanetary disks can provide valuable insights into the processes involved in planet formation and the diversity of planetary systems in the universe.