This article is about the celestial phenomenon. For a list of constellations, see Category: Constellations.
Constellations are perceived pictures formed by grouping stars together in a "connect-the-dots" fashion. The stars themselves, of course, are a huge distance from each other and usually not related in any fashion. Constellations vary widely from planet to planet due to the varying vantage points and which ones are visible usually depends on time of night and year due to orbit and rotation.
Constellations are usually identified early on in a sentient species' development as a result of having nothing better to do than sit around the campfire after a long day of hunting and gathering. The images seen in the stars depend on the mindset and culture of the observers and often form the basis of oral legends and myths, sometimes "explaining" how a particular hero got himself placed in the sky. Constellations provide valuable navigation aids for people on long-distance overland journeys and, later in their development, for space travelers. There is also a psychological benefit to recognizing familiar stars while away from home, although if one is lost several light-years away this doesn't work.