The Verse of the six films in KevinSmith's New Jersey Trilogy. It is virtually identical to the "real" world save for a few key differences — some hidden (active divine and infernal forces) and some visible ("Mooby's" fast food chain and several other multinational corporations). And the occasional giant poop monster.
The Askewniverse films are as follows:
The comic series Chasing Dogma, which bridges Chasing Amy and Dogma, and explains just how Jay and Silent Bob ended up in Illinois;
Various director commentaries point out things never explained in the film, like Brodie Bruce and Randal Graves' relationship (they're cousins), or that Rick Derris is Jay's older brother.
Anachronic Order: Mallrats is the second film in the series, but actually occurs on the day before the events of Clerks. The rest of the films are chronological, but the comics are set at points throughout the history (one of them is actually the earliest occurring story). And no one knows when - or even if - the animated series fits in.
Brand X ("Nails" cigarettes, Chewlie's gum and Mooby's restaurants, among others)
Cameo: Jay and Silent Bob have a short cameo on the movie set of the Show Within a Show "Stab" in Scream 3. Then, when in ...Strike Back, they interrupt the filming of a fictional Scream sequel to rescue their monkey.
That scene is a lot funnier since Scream 4 was released.
Deconstruction Fic: The fandom tends to explore the dark side of Jay and Silent Bob, who are generally considered a simple comic relief duo. Themes include tragic back-stories to explain Jay's outlandish behavior and Bob's silence, the realities of drug use/abuse, and the angst of being secretly in love with your best friend. The Reality Subtext also comes into play.
Executive Meddling (A positive example: the original ending of Clerkshad Dante killed by a robber.)
He definitely wasn't supposed to be there today.
Also, when making Mallrats, Kevin Smith had to fight like hell to keep Jason Mewes in the role as Jay, and it paid off.
The Ghost: Cousin Walter mentioned by Randal and Brodie is the subject of many stories but is never actually seen or heard from in any of the films.
Probably because he died sometime before the films' continuity takes place. Randal's first story about him actually details the events of his death.
Good Adultery, Bad Adultery: Usually played for laughs of the 'ex-girlfriend cheated on the hapless hero' variety - Caitlin cheated on Dante a lot (mostly with painters), as did Gwen with T.S, though Gwen at least seems too feel a bit guilty.
Fanservice: Joey Lauren Adams topless in Mallrats.
Eliza Dushku, Ali Larter, Shannon Elizabeth and Jennifer Schwalbach-Smith in Spycatsuits in ...Strike Back.
Jay doing a Silence of the Lambs tribute striptease in Clerks 2. Sadly instantly becomes Fan Disservice when it cuts to him fully nude and posing like Buffalo Bill, but the start ... Ooh, chapstick.
Salma Hayek playing a muse turned stripper in Dogma.
Ho Yay: Most of the two male platonic couples revel in this. In Chasing Amy, it's actually addressed by the plot; and it's lampshaded in Dogma. Mallrats was supposed to have quite a bit more of this, but Executive Meddling left a lot of it on the cutting floor.
It Will Never Catch On / Vindicated by History (Kevin Smith was told during production of Mallrats that a gag where semen gets stuck in Joey Lauren Adams' hair had to be cut. Because it was gross, would never sell and it would doom the movie, etc. Except for, you know, that other movie that did it three years later and grossed over $350 million freakin dollars.)
Punny Name: In Jay and Silent Bob Strike Back, Federal Wildlife Marshal Willenholly is named for the characters Marshall, Will and Holly on the 1970's children's TV show Land of the Lost.
Also, Jay and Silent Bob Strike Back is essentially one long parade of cameos, with nearly every single one of them accompanied by a Shout Out to that person's most famous previous movie role. That, and the bong-lightsaber scene.
Look kids, it's Mark Hamill! [applause]
In fairness, he did that because test audiences failed to recognize Hamill.
Thematic Series: The only direct sequel in the series is Clerks II. The rest of the series is loosely knit around New Jersey and the citizens of Red Bank.
Chasing Amy was in the works as a studio movie starring David Schwimmer, Jon Stewart and Drew Barrymore, but Kevin Smith opted for more creative control and much lower budget.