Why are stars grouped in constellations?

People who gazed at the skies in ancient times believed that they could see the shapes of animals and peoples traced out in the stars. These star groups, or constellations, have the Latin names of the shapes, and astronomers use the names in identifying stars. But the stars in a constellation do not belong to any actual group in space and may be far apart. The twelve constellations lying on the ecliptic, the sun’s path through the sky, are called the zodiac.