What is the outermost layer of skin known as?

The outermost layer of skin is known as the epidermis. This layer plays a crucial role in protecting the underlying tissues from environmental damage, pathogens, and water loss. The epidermis is composed mostly of keratinocytes, which produce keratin, a protein that strengthens the skin. Additionally, the epidermis contains melanocytes that give skin its color and help protect against UV radiation, as well as other cells that are important for immune defense.

In contrast, the dermis, which lies beneath the epidermis, is a thicker layer that contains connective tissue, blood vessels, and nerve endings, providing support and elasticity to the skin. The pustule is not a layer of skin but rather a small, inflamed, pus-filled lesion often associated with acne or other skin conditions. The subcutaneous layer, also known as the hypodermis, is located beneath the dermis and is primarily composed of fatty tissue that helps insulate the body and absorb shocks. Understanding these layers is fundamental to skincare and aesthetics, as each plays a distinct role in skin health and appearance.