I have noticed that we have got three tags with very similar topics:
(Only very few questions are tagged by more of them.)
I see a large overlap, surely between typesetting and typography. To me, it seems that these two topics are identical, and refer to the same thing: How to change the "raw text" into "typeset text", and I suggest these two to be synonymised.
I'm not sure though about formatting, I can see some differences between formatting and the other two tags; formatting is more general and can refer to more than just "putting text on paper". However: (1) the difference is small and probably quite subjective; (2) people do not distinguish the tags, it more seems that they simply choose one of the three tags for their question, quite arbitrarily. But as I say, I'm not sure.