What is meant by scale?

Scale:

1. An animal's outer layers of skin consist of a little plate or shield called a scale.
2. The animal's scales shield it from environmental hazards and predators.

Types of scales:

1. Horny scutes, also known as corneoscutes, are produced from the upper, or epidermal, skin layer in reptiles and on the legs of birds.
2. Underneath crocodilians' and certain lizards' external scales are skeletal dermal scales called osteoderms.
3. Epidermal scales that have undergone developmental modifications are what birds' feathers are.
4. Some animals, such as rats and pangolins, have scaly surfaces that are generated by modified epidermal tissue, which is mostly composed of keratin.
5. Mammalian hair is mostly made of keratin, however it is not a modified scale.