Skin covers the outer surface of the body and is the largest organ. Skin and it’s accessory structures (hair, sweat glands, sebaceous glands, and nails) make up the integumentary system. Its primary functions are to protect the body from the environment and prevent water loss.

Skin is classified into two types:

Thick skin – covers the palms of the hands and the soles of the feet
Thin skin – covers the rest of the body
Skin consists of two layers:

Epidermis – outer layer of stratified squamous keratinized epithelium
Dermis – underlying layer of dense, irregular connective tissue that contains other structures (such as hair follicles and sweat glands)
Deep to the dermis is the hypodermis, a layer of varying thickness of loose connective tissue and adipose tissue.