The rhinoceros, commonly known as a rhino, is a large, thick-skinned herbivore found primarily in Africa and parts of Asia. There are five species of rhinos: the white rhino, black rhino, Indian rhino, Javan rhino, and Sumatran rhino. They are characterized by their distinctive horns, which are made of keratin, the same material as human hair and nails. Rhinos play a crucial role in their ecosystems by helping to maintain the balance of vegetation. Unfortunately, they are threatened by habitat loss and poaching for their horns, which are highly valued in some cultures. Conservation efforts are ongoing to protect these magnificent animals and their habitats.