The term "human skin" refers to the outer covering or integument of a human body. It is composed mainly of two layers - the epidermis and dermis, with subcutaneous tissue beneath it. The primary function of the skin is to protect the internal organs from external harm, regulate temperature, provide sensation, and act as a barrier against infection. Human skin also plays an important role in non-verbal communication through expressions such as facial gestures, body language, and touch.