I'm not sure from your question but do you mean LPs.
If that's what you mean then LP stands for Long Player. In other words a vinyl music album that typically had 8-10 music tracks on each side of the record. LP (long player) was a whole album. There were also singles, with one song on each side of a smaller sized record and an EP (Extended Player) that would typically have two songs on each side of a record but was the same dimensions as a single.
These records would be played on a record player (previously known as a gramophone). All of this predates the CD and was most popular up until around 1980.
That's shown my age!