A phonograph record , a vinyl record , or simply a record or vinyl is an analog sound storage medium in the form of a flat disc with an inscribed, modulated spiral groove. The groove usually starts near the periphery and ends near the center of the disc. For about half a century, the discs were commonly made from shellac, with earlier records having a fine abrasive filler mixed in. Starting in the 1940s, polyvinyl chloride became common, the "vinyl records" of the late 20th century.