Which layer is the outermost layer of skin?

The epidermis is the outer (epi in Greek meaning "over" or "upon") of the two layers that make up the skin (or cutis), the inner layer being the dermis.[1] It provides a barrier to infection from environmental pathogens[2] and regulates the amount of water released from the body into the atmosphere through transepidermal water loss (TEWL).[3] The outermost part of the epidermis is composed of stratified layers of flattened cells,[4] that overlies a basal layer (stratum basale) composed of columnar cells arranged perpendicularly