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I'm currently playing a DnD 3.5 campaign and the only sources we are currently using are: the PHB, the Dungeon Master Handbook, the Monster manual.
Now there seem to be a lot of other books out there, some belonging to DnD 3.5, some not. I'm a bit confused as towards how it all works. I understand of course that we can just choose what books to use. But which books are considered part of DnD 3.5? And is there a difference to DnD 3.5e? (i.e. what does the e stand for?)