An extended play or EP is a musical format (vinyl record, compact disc, audio cassette, etc.) which is too long to be described as single but too short to qualify as an album (or LP). … A remix of a single song is not an EP unless it contains in addition to other songs that do not remix. It is something between a single and a full CD (or LP); a little too short to be a full CD and a little too long to be a single. It usually has 3-5 tracks. Estimated length that the industry gives is 25 minutes or 5 tracks. And there have been numerous double EPs released over time.
LP (LONG PLAY) refers to Long Play; it is a vinyl record; this is a collection of music that qualifies as a full album release. Usually 40 minutes or 10 tracks at the minimum. There has been multiple disc albums up to 4x released in history. The LP (Long Play), or 33 1⁄3 rpm microgroove vinyl record, is a format for phonograph (gramophone) records, an analog sound storage medium. Introduced by Columbia Records in 1948, it was soon adopted as a new standard by the entire record industry. Apart from relatively minor refinements and the important later addition of stereophonic sound capability, it has remained the standard format for vinyl albums.
ALBUM- What an album is today is an LP that is promoted and sold where one can keep track; also count towards a record contract to being completed. Albums are made by artists but controlled by record labels on every level; even the creation process.
MIXTAPES- These have become underground albums today that are given away for free containing both original and unoriginal works. The sole purpose is to build a fan base not profit. Typically the artist is in complete control of this project so they decide the length, content, etc.