Flags serve many purposes. They symbolize a people and represent national pride. Flags convey a shared history. Over the centuries, military units have carried flags and colors. Colors and flags affirm group identity. They build pride and morale, and represent the group's honor. In battle, flags served as a rallying point when a formation was broken. Troops gathered around the flag to regroup, attack or retreat. Flags marked specific individuals, locations and functions such as hospitals and ambulances.