If you want to do some more than just making the simplest of descriptions you might help fleshing out monsters, npc's, dungeons, items and quests.

The descriptions add the flavor but we also need paramters to go along. For example a monster does not only consists of it's plain description but we need descriptions fo various occasions.

Check the forum section: Creating the World of Gondor

Quests are actually a combination of monsters, npc's dungeons, items, rumors and even other quests. You can for example design a dungeon, a monster and an item and then build a quest around those elements. Quests can be designed by specifying which certain elements and goals are needed to fullfill a certain Quest.