To humans, half-elves look like elves. To elves, they look like humans. They’ve inherited characteristics from both sides, but don’t truly belong to either.
Half-elves don’t have a culture or lands of their own. A half-elf will find him or herself welcome in human cities, and maybe a bit less welcome among the elves. Some avoid company entirely, though, preferring to live as hunters, trappers, or adventurers on the fringes of society.