Dermatology is the branch of medicine dealing with the skin and its diseases, a unique specialty with both medical and surgical aspects. A dermatologist takes care of diseases, in the widest sense, and some cosmetic problems of the skin, scalp, hair, and nails.

Coined in English 1819, the word dermatology originated in the form of the words dermologie (in French, 1764) and, a little later, dermatologia (in Latin, 1777). The term derives from the Greek "δέρματος" (dermatos), genitive of "δέρμα" (derma), "skin" (from "δέρω" – dero, "to flay") + "-logy, "the study of", a suffix derived from "λόγος" (logos), amongst others meaning "speech, oration, discourse, quote, study, calculation, reason", in turn from "λέγω" – lego, "to say", "to speak".

Readily visible alterations of the skin surface have been recognized since the dawn of history, with some being treated, and some not.^{[citation needed]} In 1801 the first great school of dermatology became a reality at the famous Hôpital Saint-Louis in Paris, while the first textbooks (Willan's, 1798–1808) and atlases (Alibert's, 1806–1814) appeared in print during the same period of time. In 1952, Dermatology was greatly advanced by Dr. Norman Orentreich's pioneering work in hair transplantation.