"Lore" is the general term used in LOTRO to refer to Professor Tolkien's original body of work, including The Hobbit and The Lord of the Rings. In general, the game designers have tried to adhere to the original lore as much as possible, while still creating a marketable product. During the beta phase of development, "lore violations" were actively solicited and resolved wherever practical.
Examples of lore include:
- Tom Bombadil's jacket is blue
Lore in an MMORPG
Some aspects of the Lore are simply impractical in an MMORPG. For example, Middle-earth as described by Professor Tolkien was a pretty empty place, and encounters with hostile monsters were relatively rare, except in a few places like Moria. It would not be practical to develop an MMORPG with no monsters, so Eriador has more hostile orcs than one might assume from reading The Fellowship of the Ring.
Lore on Lotro-Wiki