2. Music recorded on vinyl records.
Vinyl records were predominantly recorded in 33 or 45 rpm. They were not as fragile as the 78 rpm records they replaced. Sizes were 7 and 12 inches diameter. A 45 rpm 7 inch was called an EP or single, because it held a single song on each side. A 33 rpm 12 inch was is an LP or long-playing? record, with 5 or 6 songs on each side. In the 1980s, vinyl records were gradually replaced with the CD or compact disc.