To put it succinctly,
A ‘nudist’ is someone who likes to suntan on a beach, in their backyard, or at a club or resort, for several weeks of the year.
A ‘naturist’ is someone who legally lives in the nude at every opportunity, and engulfs a belief in the integration of humans with, not against, nature.
That’s it. Just note that a transition from one to the other can happen.
Children born into naturist families most always stay as naturists for the rest of their lives.
Children whose parents are ‘occasional’ nudists, may or may not, become nudists.
So once a naturist, always a naturist, but once a nudist, sometimes a nudist.
And there are estimated to be over 33 million practising naturists around the world, and over 70 million nudists who frequent nudist resorts in over 104 countries.
Many people live in the nude and their neighbours never know.