Short answers, pulled from the story.
The world received two compact discs titled Past Masters Volume One and Past Masters Volume Two on the 7th of March 1988. This release marked the first time the entire Beatles catalogue appeared on the new digital format.
Volume One gathered recordings originally released between 1962 and 1965 including eleven tracks from British singles and four additional tracks from the Long Tall Sally EP. The set also featured both tracks from the German single Komm Gib Mir Deine Hand / Sie Liebt Dich and a US-only track called Bad Boy.
Mark Lewisohn, a noted historian of the group, organized the collection into two distinct volumes. He also wrote the liner notes that accompanied the initial pressings before his name disappeared from the credits on the 2009 reissue.
Volume Two contained fourteen tracks emerged from British singles including various B-sides and a version of Across the Universe recorded for the charity album No One's Gonna Change Our World known as the Wildlife version. These tracks filled gaps left by the core studio discography until their breakup in 1970.
The combined CD titled simply Past Masters arrived on the 9th of September 2009 following remastering for digital distribution. Stereo mixes replaced mono versions for From Me to You and Thank You Girl during this process.