Photograph of a man with a moustache dressed in women's clothing; he is wearing a costume with corset type doublet and hose, and is carrying a whip. Photograph from 1896 by Richard von Krafft-Ebing (1840-1902), an Austro-German psychiatrist and author of the foundational work Psychopathia Sexualis. This book popularized the terms sadism (derived from the brutal sexual practices depicted in the novels of Marquis de Sade) and masochism (derived from the name of Leopold von Sacher-Masoch), although these terms were in use prior to its publication. Psychopathia Sexualis was one of the first books about sexual practices that studied homosexuality/bisexuality.