Arwen, the daughter of Elrond and the love interest of Aragorn, was a half-elf. She had both the immortality and magical abilities of an elf, but also the mortality and human-like qualities of a human. Her father, Elrond, was a powerful elf who had lived for thousands of years, but her mother, Celebrian, was a human. This made her a "half-elf," and she had the choice to remain immortal like her elven father or to become mortal like her human mother.