Playlists & albums are a way of grouping your beats and/or songs and are found in Dashboard > Music & Media > Playlists & Albums. These are only available with the Platinum Producer Package and whilst playlists can be displayed in any store, retail collections can only be displayed in your HTML5 Store. There are 3 types of retail collection:
Beat Tape: This is a collection of your beats that you can sell as a whole unit, rather than selling the beats individually. Beat tapes come with a contract and the files are leased, the same way individual beats are leased
Mixtape: This is sold as a whole unit, for listening purposes, and not leased like beats.
Album: Albums can only contain songs, and are sold as a whole unit, for listening purposes, and not leased like beats.
Unlike the 3 above, playlists are not for sale. Playlists are simply a way to display a group of beats (e.g a hip hop playlist) in your Music Store. This is a great way to segregate your beats if you want to display different genres, type beats, license types, etc.
Individual beats can be bought directly from the playlist, however the playlist cannot be bought as a whole collection.