Like the CD album, the CD single came into being around 1982 and was create jointly by Sony and Philips. The CD Single replaced the 7 inch vinyl record and was used to calculate the charts until recently when downloads took over. The CD single usually carries 3 songs which consists of a main recording plus 2 further tracks which are similar to the old B Sides which appeared on the 7 inch vinyl record. It is quite common to have the main song followed by other versions of the same song. For example a dance version or an acoustic version or a re-mix or even an original demo version. Planet Earth Records have a large stock of single format CD's.