Compress Design vs: Compress Options tool

Is there anything out there that tells the difference between a plane "File > Compress > Design" and the "File > Compress > Options"? In other words, what does the "Compress Design" tool do, that the "Compress Options" doesn't. I know Compress Design removes deleted data stored in the file (Undo buffer) that the Compress Options does not! What is some of the other junk data it removes? Also what does the Compress Design do, that the option in User Preferences to "Compress on Exit" doesn't. I am trying to explain the differences to my users.