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For thousands of years, human beings have used the night sky to navigate, keep track of the seasons, and inspire myths and legends. The tradition of naming stars is as old as history itself. Before modern times, however, humans could only name the stars that were visible in the night sky--a tiny fraction of the number of stars we can see today with powerful telescopes. Some stars have beautiful and evocative names, while some stars are designated by unimaginative-sounding groups of numbers and letters. So how do stars get their names? Today, most stars are not given proper names. However, a few stars have kept names given many years ago. Here are a few ways a star may have come by its name. Tradition. Some stars stand out from the rest. These "stars among stars" have been singled out with traditional names for centuries. Polaris, for example, is the one star that seems to occupy a fixed position in the heavens. People have been using it as a navigation aid for millennia, and it has had many different names in various cultures. In addition to Polaris, Western culture occasionally refers to it as the North Star or the Pole Star. Ancient star catalogues. Some star names have been preserved in the works of ancient astronomers. Perhaps the earliest star catalogue we know of was written by Gan De, a Chinese astronomer who lived in the 4th century BC. The Western world's first star catalogue was written by Timocharis, an astronomer from Alexandria, about a hundred years later. Most of the ancient star names still in use today, however, can be traced to the 2nd century AD. Ptolemy, a Greek mathematician and astronomer who lived in Egypt almost two thousand years ago, wrote a star catalogue in The Almagest, a mathematical and astronomical document outlining star and planetary motions and mechanics. Ptolemy's catalogue contains over a thousand stars. Most of these are identified first by their position within a certain constellation; second by their longitude and latitude; and third by their magnitude, or brightness. He did give a few stars special names, most of which are in common use today. These include Arcturus, Sirius, Regulus, Capella, and Spica.