Nebula is a term used to describe an interstellar cloud of dust, hydrogen, helium, and other ionized gases that scatter light and create a breathtakingly beautiful visual display. These cosmic clouds can vary in size and shape, ranging from small and compact to large and diffuse. Nebulae are fascinating objects to study for astronomers, as they offer insights into the birth and death of stars, the evolution of galaxies, and the nature of the universe.