The ancient Greeks saw many other constellations that we still use today. The saw Ursa Major the Great Bear, Leo the Lion, and Corona the Crown.
When Europeans began exploring the Southern Hemisphere, they saw different stars, which made new patterns. They began naming Southern hemisphere constellations. They called one Crux,the Southern Cross. They called another Centaurus, the Centaur. They even named one constellation Microscopium, the microscope!
Astronomers today recognize 88 constellations. When astronomers talk about something in the sky, they often name it after the constellation it is closest to. For example, the large spiral galaxy M31 is near the constellation Andromeda. Astronomers call it the Andromeda Galaxy.