EP - Extended Play, a short album that usually has about 3 - 6 songs.
SP - Single Play, a CD, tape, record, etc. that has only one song, (a single) on it. In some rare cases, it can have 2 or even 3 songs on an SP.
"And I thought how what a beautiful thing because maybe one day it will be like that. You know what I'm saying? Maybe one day it will be that..." <can't control his laughs> "Wow, SPs, like, they'll just read about those in the history books, you know." --Tom Cruise
Johnny; Judy? Fine no problem.