First Edition: The genesis of tabletop RPGs as we know them, or as I like to call it, “Paper Dark Souls”. The entire party will probably get killed by a Sphere of Annihilation disguised as a chest while Gary Gygax laughs at you from the afterlife. Had way too many fucking books.
Greyhawk: The Great-Grandpa setting from which everything else was spawned. Seems pretty generic, but only everybody else copied it. Mostly played by hardcore nostalgics who only accept the oldest of old-school.
Mystara: Greyhawk but with more stuff. Not especially interesting despite being one of the first settings.
Jakandor: Native American-esque Vikings invade a post-apocalyptic island of Japanese-Aztec necromancers and lots of war ensues. In other words, it’s a game about conflict between colonials and natives and that’s all it really has going for it.
Planescape: Go adventuring through a giant city in the center of the multiverse and have weird-ass shit happen to you! Pretty much DND’s attempt to copy White Wolf and be “punk” in the 90’s, but managed to be cool despite that.
Ravenloft: DND, as written by every 19th century Gothic writer ever. Go on an adventure in the personal hells of a bunch of sad assholes, though you’ll mostly just be moping around and contemplating your navels like a high schooler who’s read too much Edgar Allen Poe.
Spelljammer: Dungeons And Dragons… IN SPACE! Pretty much the greatest Treasure Planet game that was never made.
Basic DND: John Eric Holmes proves he’s more merciful than Gary Gygax by making a beginners DND for the kiddies.
Pelinore: By jove, good lads, it’s DND for the Brits! So boring and whitebread that Britain is literally the only country that cares about it.
Birthright: The gods blew each other up, raining their precious fluids all over and giving heroic mortals divine energy, but you don’t play any of those cool guys, you’re their dipshit royal descendants. More of a wargame/politics simulator than an RPG.
Council Of Wyrms: If you ever thought it was bullshit that you didn’t play as dragons in a game called “Dungeons and Dragons”, this is the game for you!
Dark Sun: Fantasy Mad Max. The sun’s dying so everybody says YOLO and kills each other over water. Also, Mantis-Men. Makes very little sense at times, but is awesome nonetheless.
Dragonlance: Margaret Weis and Tracy Hickman forget that they’re making a game and write a sprawling novel series. Completely dominated by it’s fluff. A surprisingly decent setting, but unfortunately it created the Kender and must therefore be banned as a heretical text.
Forgotten Realms: One of the longest running and most influential DND settings out there. Manages to be pretty good when it’s not too busy being a vehicle for Ed Greenwood’s Mary Sues and sexual fetishes. Elminster probably fucked your mom shit lips.
Second Edition: Solidifies and introduces a lot of great stuff, despite Lorraine Williams’ best efforts to the contrary. The rules are broken as hell due to a lack of playtesting, so have fun with exploits like turning peasants into living railguns. Bigger focus on fluff and roleplaying, but don’t worry, the game is still obsessed with murdering your character.
Third Edition: Friendship with TSR ended, now Wizards Of The Coast is my best friend. The writers make the bold and staggering decision to focus on making the game actually fun instead of torturing players.
Blackmoor: The prototype for DND that became it’s own setting… until it’s copyright status turned into a jumbled trainwreck and it got dropped like a hot potato. Mostly made up of fan works by now.
Eberron: Keith Baker wins a contest and makes the coolest DND setting ever, bless him. Your characters will inevitably turn into Indiana Jones by the end of any given session.
Ghostwalk: The criminally underrated setting that nobody knows about. Play as a ghost and get up to all sorts of ghost antics in the lands of the living and dead.
Fourth Edition: New Coke, the RPG. People spend more time arguing about this than actually playing it. You’ll have to do so much fucking math it’s not even funny. Actually tried to experiment and do something new, to its credit.
Nentir Vale: The boring, uber-generic default setting for 4E. Designed to be a blank slate that you personalize, which sounds good, but I honestly have not met many people that play it often.
Pathfinder: Paizo thinks 4E sucks and decides to make it’s own DND Edition, with blackjack and hookers! The setting is an insane, all-encompassing mishmash of every fantasy thing ever, yet still manages to be pretty good. Really fun and well-made, as long as you’re willing to push through the periodic, bumbling attempts to be “edgy” and “woke”.
Starfinder: Pathfinder… IN SPACE! Not much to say about it; it’s pretty much the Pathfinder version of Spelljammer.
Fifth Edition: Coca Cola Classic, the RPG. Tries really hard to be a polished culmination of everything good about DND, and more or less succeeds. You’ll still see endless bitching and moaning about it. Also, the release rate of books makes George RR Martin look like Speedy Goddamn Gonzales.
Ravnica: Wizards Of The Coast says fuck it and makes a DND/MTG crossover.
Dragonmech: Have you ever thought, “good golly this game would be way better with giant robots”? Then you’re gonna fucking LOVE this, son! You are legally required to sing mecha anime theme songs while playing.
Dragonstar: Wizards Of The Coast makes a whole new Space DND instead of just making new Spelljammer stuff.
Kingdoms Of Kalamar: The guys who made Knights Of The Dinner Table decide to make the most primitive, low fantasy DND setting physically possible. Have fun playing as a literal farmer!
Pathfinder Second Edition: Paizo decides that maybe 4E didn’t suck that much and starts stealing the good bits from it. Not much to say about this either, it’s mostly just updating rules and stuff, plus some more clumsy efforts to look woke.
The Adventure Zone/Critical Role: If you’re sufficiently young, there’s a pretty good chance these are the only reason you got into this hobby.