In radio broadcasting, a spin is a single play of a song. The term is also used as a unit to measure (or induce) popularity, typically in spins per week. This measure is also known as rotation, and is most heavily used at Top 40 radio stations, some non-traditional radio formats, and others with descendant radio formats. A song in light rotation is typically aired 5–15 times per week, while a medium rotation tune goes over the airwaves 10-25 times per week. Favored songs in heavy rotation start at 20 or more spins each week, perhaps reaching to 50 and beyond. This results in several spins each day, resulting in a high level of repetition for listeners who tune in for more than just a short amount of time. Most new songs end up in the heavy rotation category, but as the song gets older it is eventually downgraded from heavy to medium, then to light, then to retirement.
