text: Terms from the days of vinyl records. As I worked in a record store selling Vinyl for 2 years during the 80s, I got to work intimately with them... so...\n\nLP = Long Play (full length album) - 33 1/3 speed\nEP = Extended Play (as in extended from a single) - 33 1/3 speed\nSingle = one song a side - 45 speed\n\nLP records could be a maximum of about 40 minutes with microgrooving, less without.\nEP records were from 3-20 minutes (as I recall).\n\nAn LP could hold 5-6 songs per side.\nAn EP could hold 1-3 (cramped at 3) per side.\nA single could hold one song per side.\n\nHow they were used.  Bands generally used LPs for full length album releases.  EPs were used commonly to release a short album release (a few songs or extended remix singles).  The EP format was also typically used on 12" singles.  12" singles also ran 33 1/3 speed.  45's (singles) were obviously used to release two songs from an album (not usually remixes).\n\nSizes for vinyl include 12", 10" and 7" diameter.  EPs could be 10" or 12".  LPs were only 12".  45's were only 7".  \n\nAnd finally, there were picture disks.  These were a special process to overlay the vinyl grooves on top of a picture.  They were generally heavier and the vinyl didn't hold up as long.  Picture disks were, as I recall, always 12" in size.