From the introduction:
The Unified Setting is a low fantasy setting focusing primarily on politics and religion, with less emphasis than usual on traditional dungeon delving, although certain historical sites are designed to supply dungeons as needed. The setting as a whole receives considerable criticism as "furry" due to the prevalence of beast races.
The peculiar site 1d4chan.org hosts a variety of fan-created projects for roleplaying game support. The Unified Setting is a sprawling, complex, and bizarre setting used across the site for many (not all) game efforts. The setting is defined by a large number of topical pages. Most of the setting is system neutral; the setting has been specifically adapted to D&D 4e, however.