Hoof
Appearance
![](https://cdn.statically.io/img/upload.wikimedia.org/wikipedia/commons/thumb/f/fc/Masai_Giraffe_right-rear_foot.jpg/200px-Masai_Giraffe_right-rear_foot.jpg)
A hoof is the foot of certain animals known as ungulates (such as deer, cows, pigs, sheep, and giraffes). These animals walk on their toes. The toes have a hard cover made out of the same material as fingernails. This is called keratin.