Elfs are medium-true fey and can never die of old age. Most of the elfs are centuries old and impossibly powerful and hyper-competent. They’re also pissy and jaded. These elders are organized into Nations (cliques) according to geomantic, political, and philosophical divides too nuanced or esoteric to make sense to any outside observer.
The minority of elfs at the Player Character level are “uncool teenagers” (typically under 100) who have yet to accomplish anything worthy of notice by any of the Nations. The main motivation for adventuring is to get noticed by sempai and move up the elfish social ladder.
Elfs have no written language, since it’s assumed that if an elf really needs to know something, he can set aside fifty years and figure it out. If he’s really desperate, he can find and ask an elder, but they’re not going to do do anything unless you make it interesting for them. Which is difficult because the elders are all extremely jaded.
All of this is completely nonsensical to humans. All they know is that you stay out of Elf Nation territory, or the elfs eat you (this is largely a rumor – most of the Nations currently feel that eating people is uncool). Sometimes the younger elfs get out into the wider world, and they do good work, but they’re unreliable and might eat your kids.