The skin is the largest organ in the human body, and it is composed of three main layers: the epidermis, dermis, and hypodermis.
The epidermis is the outermost layer of the skin and is primarily composed of keratinocytes, which produce the protein keratin. This layer provides a barrier to protect the body from external factors such as harmful chemicals, pathogens, and UV radiation.
The dermis lies beneath the epidermis and is made up of collagen and elastin fibers, which give the skin its strength and elasticity. This layer contains blood vessels, nerves, hair follicles, and sweat glands.
The hypodermis, also known as the subcutaneous layer, is the deepest layer of the skin. It is composed of adipose tissue (fat) and connective tissue, which help to insulate the body and protect the internal organs.