Here's a very handy-dandy chart of the different Discworld storylines, the closest thing to a 'chronology' you'll get. It's missing a lot of the later books (Making Money, Raising Steam, and Snuff come to mind).

Spoiler
Show


The Rincewind/Wizards books follow Rincewind the cowardly Wizzzzzard, his Luggage (capital L), and the assorted faculty of Unseen University. Lots of lampooning of fantasy novel tropes, with a heavy dose of school/university-related humor and some social commentary at times.

The Witches books follow Granny Weatherwax, Nanny Ogg, and a few others, solving problems with as little magic as possible. Also parodies of fantasy stories, but with a different angle than the Wizards books since witches are generally much more level-headed and competent.

The Death books follow the anthropomorphic embodiment of (obviously) Death, its assistant Alfred, and its daughter Susan (it's complicated). Generally a mix of social commentary and exploring aspects of what it means to be human, for good or bad.

The City Watch books follow the Watch of Ankh-Morpok - Sam Vimes, Carrot Ironfoundersson, Nobby Nobs, and the rest. They live out pretty much every police procedural, detective novel, or crime story you can imagine with the typical Discworld zaniness to mix things up.

The Moist books are about a "reformed" swindler and con-man, who gets caught up in becoming responsible for various modernizing technologies and social trends in Ankh-Morpok. Starts with Going Postal, though there are a number of standalone books predating Moist along the same theme.