A unicorn looks like a horse with a horn growing out of its forehead. Unicorns are known to be attracted to innocence.
In Phaze Edit
Unicorns in the Apprentice Adept series are somewhat different from traditional unicorns. They are as intelligent as humans, have more dramatic coloring, are shape shifters, and have hollow horns which produce musical sounds.
Should a unicorn's coat have socks, the socks can be removed and donned by others. While a non-unicorn is wear a unicorn's socks, they are covered with the illusion of being a unicorn the color of the socks.
Unicorns can learn to shape shift into up to two other forms. Should the form be a bird, the unicorn can fly; or if the form is human, the unicorn can speak.
The musical sound produced by the horn of a unicorn is a specific musical instrument such as a harmonica or flute.
In Xanth Edit
Unicorns in Xanth are mostly like the unicorns in other fantasy settings.