We just looked at the emission spectrum of light for hydrogen, helium, and neon. This represented the light given off or emitted by each element.
When scientists use telescopes to look at stars, they are studying the light given off by stars. The interior of a star produces a continuous spectrum of light, like a rainbow. Cooler gases in the outer layers of the star absorb certain wavelengths of light, causing dark lines to appear in the spectrum. The resulting absorption spectrum can tell astronomers a great deal about the star.