An open cluster is a group of stars that are physically close to each other in space and share a common origin. These clusters typically contain a few dozen to a few thousand stars, which are held together by their mutual gravitational attraction. Open clusters are often found in the Milky Way galaxy and are relatively young compared to other star groups, usually ranging from a few million to a few hundred million years old. Open clusters are important for studying stellar evolution because they provide a snapshot of stars that formed around the same time and from the same material. Examples of well-known open clusters include the Pleiades and the Hyades. Observing these clusters helps astronomers understand the processes that govern star formation and the dynamics of stellar populations.