World
A world is a claimable OWOT URL. For example, /exampleworldforwiki.
To claim a world you need to have an account. Guest accounts cannot own worlds.
World Settings
World owners can change world settings such as themes, colors, background colors, world members, etc.
However, admins get extra world settings, like changing the background image of the world and setting a script to be automatically run when a world is entered.
Advanced world settings
If you click "Advanced" under "Miscellaneous", you'll be able to change advanced settings such as cell dimensions, write intervals, rate limits, meta descriptions, private notes, NSFW status (barely used), logging edits, disabling global chat, limiting copying and a membership key.
World claiming and shown worlds
If you have an account and go to your profile, you can see a list of your claimed worlds and an input box which allows you to claim a world.
WOTD
Worlds can be requested at /fp/submit to get added to the poll so they can become a WOTD.