The epidermis is the outer layer of what human organ?

The epidermis is the outer of the two layers that make up the skin (or cutis; Greek δέρμα derma), the inner layer being the dermis. It provides a barrier to infection from environmental pathogens and regulates the amount of water released from the body into the atmosphere through transepidermal water loss (TEWL). The outermost part of the epidermis is composed of stratified layers of flattened cells, that overlies a basal layer (stratum basale) composed of columnar cells arranged perpendicularly.

In addition to rows of cells, the epidermis also contains hair follicles, and two types of sweat glands: sebaceous glands and eccrine glands. These cells develop from the stem cells in the basal layer of the epidermis.