Nudism can be differentiated from the practice of spontaneous or private nude bathing ("skinny-dipping") in that it is an ongoing, self-conscious and systematic philosophy or lifestyle choice, rather than a spontaneous decision to disrobe.
Nudism was known by many names: in Germany, as Nacktkultur, Freikörperkultur (free-body culture), or Lichtkultur (light culture); in France as nudisme, naturisme, or libre-culture (free culture), and in England as Gymnosophy or naturism.
Scientists and physicians saw nudism not as a return to Eden (although this trope certainly occurred in nudist writing), but as a path forward to a shining new modernity in which science, rather than superstition, would lead the way.
The so-called "father of nudism" was the German Heinrich Pudor (real name Heinrich Scham), who coined the term Nacktkultur ("naked culture") and whose book Nackende Menschen (Naked man [1894]) was probably the first book on nudism.
While nudism had distinctive national flavors, and there was occasionally some rivalry (especially between the French and the Germans), there was also considerable communication, influence, and overlap between nudist cultures.
Ennemond Boniface was a socialist nudist, who fervently believed that nudism was an alternative to bloody socialist revolution, and would bring about a new naturist era in which all would be equal under the sun (see sidebar).
By and large however, nudism was a movement endorsed and organized by educated people-physicians, scientists, lawyers, clergy, and, in France especially, occasionally by members of the aristocracy.
Caleb Saleeby, for example, was a fervent advocate of nudism, heliotherapy, and eugenics (he was Chairman of the National Birthrate Commission and author of a number of books on eugenics).
Nudism has remained a minor practice, and it has by and large mutated into a "lifestyle" chosen by individuals rather than either a medical practice or a program for social reform.
Nudism flourished in Germany, France, England, elsewhere in Europe, and in the United States, but its advocates often had to fend off legal challenges or accusations of depravity.