What do you need to know about a setting?

[Dhavaer]

Like many others, I expect, I'm making my own homebrew campaign setting, and am intending to put it on the homebrew forum. Unfortunately, I'm having a problem writing it down. Not because I can't think of things to write about it, but because I can't think of relevant things to write about it.
So, I put it to you: what are the most important things you need to know (probably as a player, but DMs too) about a campaign setting?

[Kaelaroth]

Basic Geography? Languages? Religion? Level? Any barred classes?

[DraPrime]

History, factions, and any details that you think might be useful. Take my campaign setting, (look in my sig) I needed a way for people to record days. So I put in a moon that circles around the world in one day. It's just one of htose little bits of fluff that your players want to know.

[Threeshades]

Basic Geography? Languages? Religion? Level? Any barred classes?

Races, sub-races, cultures and creatures too, maybe special kinds or uses of magic. I think that's it in a nutshell.

Well okay you should write some history about the relations of the different races and how it got like this. And maybe some important happenings in the world, especially its current situation (if its dominated by some evil powers or if there is a big crisis between the peoples or anything)

[Machete]

No depth needed, just skim each subject:

Races
Race Relations
Character Classes
Social and Cultural Environment (historically based, caste system, everybody is equal, is there slavery?)
Basic Laws and How Well Its Enforced Generally AND In Our Area
Town/Wilderness Ratio
Who is In Charge?- Kingdom, Area, Town
What can we buy with our PHAT LOOTZ?
Types of Magic
Rarity of Magic Items
Currency
Can I Blow Things Up and Get Away With It?
Local Menaces

[Jade_Tarem]

The basic non-magical physics, maybe? If your PC's are entering a world for the first time, and you've altered it such that air pressure goes down as elevation decreases and you've removed terminal velocity, that's good for them to know.

[horseboy]

The more story hooks you can give your players to help flesh out their characters, the deeper there characters. The deeper their characters, the more compelling the story. That is if you want a story. If you don't want a story just where is here, where is dungeon X, where do we go next.

[SITB]

How about the information that every Average Joe(A.K.A the common traveler or commoner) knows?

[MrNexx]

Like many others, I expect, I'm making my own homebrew campaign setting, and am intending to put it on the homebrew forum. Unfortunately, I'm having a problem writing it down. Not because I can't think of things to write about it, but because I can't think of relevant things to write about it.
So, I put it to you: what are the most important things you need to know (probably as a player, but DMs too) about a campaign setting?

First of all, unless you have a really good reason not to, assume that general Earth-type physics will apply... that's generally not something to mess with just because it would be "neat".

However, you can usually start in two different ways... big or small. If you start big, try drawing a map of the world. Even if you just sketch it out, figure out who lives where, and what their influence on the world is. This group of humans lives next to this group of humans who lives next to this group of orcs... maybe group A is allied with the orcs against group B, leading group B to turn into a militaristic society to fend them off? Drawing these broad strokes will help you fill out the world, and you can put the things you know you want in there in the places you know you need them.

If you start small, take one city or village and detail it. What gods are worshiped there? What goods do they produce? Who do they trade with? What intrigues are happening? From there, you expand out ward, looking at the connections which bind this community into the world. Faldor's Farm trades with Upper Gralt, and worships all the Gods equally, because they're Sendars. One of the farmhands, Brill, is a Dagashi, sent to spy on the cook, Pol, who is a sorceress in disguise. Garion is a scion of a line of kings thought dead and the only person who can fulfill a prophecy. Of course, that requires you to fill out where Upper Gralt trades with, what a Dagashi is, what a sorceress can do, and what's up with this prophecy... but you started with a small community.

[Citizen Joe]

1. What is the role of Religion in your world?
2. How many religions are there?
3. Do the gods actually make a physical presence in your world?
4. What is the role of Politics in your world?
5. How many countries are there?
6. Do humanoid monsters count as a culture (rather than just being rampaging beasts)?
7. How rare is magic use?
8. How rare are magic items?
9. How does your world differ from Earth Normal?
10. How does your world differ from DND normal?

[Fax Celestis]

Is there a metaplot? What's the country and continental histories, even if it's just a timeline? (Hell, make a timeline, as it makes history easier to reference).

[Bitter_Elf]

Citizen Joe, Machete, and Kaelaroth make excellent points. For the most part (and especially when you're just getting started), you don't need to go into great detail about every aspect of your world - instead, summarize the basic features so that your players can have an idea of what the world looks and feels like, generally. A lot of this will depend on how familiar your players are with D&D in general. If they know the PHB and DMG inside and out, just describe the differences between the D&D universe assumed in those books and your world. If they're not so familiar, you'll have to describe religion, magic, politics, geography, etc. in slightly more detail.

Of course, it always helps to have some detail to draw your characters in and create plot hooks. Pick a few aspects of your world (a particular location, race, government, person, piece of history, etc.) and describe them in more detail - you can use one as the focal point of your first few adventures, to let the players know that they really are embedded in this world, and not just running around on top of it.

Hope this helps!

[bosssmiley]

Easy.

"What is the primary unique selling point of your setting?"

Why should I play in it, rather than in any another? How does it differ from the Core and other published settings?

Eberron: "Indiana Jones with magic."
Midnight: "The BBEG has already won."
Tears of Blood: "Fallout meets D&D."
Spelljammer: "D&D in spaaaaaace!"
Al-Qadim: "Arabian Nights D&D."
Birthright: "You are king."
Forgotten Realms: "Errrr....."

What is the salient hook of the all-new, extra-shiny Dhavaer setting? All else depends on - and follows on from - that and that alone.

Having established the primary hook, you can then move onto the nitty-gritty of it. Put yourself in the position of someone who knows nothing about the setting: what will he/she need to know to play? I'd suggest using the PHB (or the SRD, or the ECS) as your template for information layout and go through each section (Races, Classes, Skills, Feats, Adventuring, Spells, etc.) in turn.

The gameworld itself? You don't *need* a 20 page gameworld bible for the players to read (and most will just glaze over in the face of such an infodump anyway). Bring the cool stuff out in play.