The healthy nudity is an intrinsic value as part of our inalienable human rights and is also in harmony with the nature. The feeling of wind, water and other surrounding will bring us close to the nature comprehensive physically and mentally to our gut reaction. It is our right and any kind of society's pressure, no one should violate our wonderful freedom. Nudism (Naturism) is a way of life that practice body acceptance, the lifestyle is about being naked and unashamed, natural, and not driven to behave improperly. The vital, practice nudism is respect human body and environment. Human body is beautiful in all shapes and sizes, accept in any bodies, go nude is form of acceptance. For the reference, from the definition of INF (International Naturist Federation) statement as naturism, at 1974 INF World Congress held in Agde, France: "Naturism is a lifestyle in harmony with nature, expressed through social nudity, and characterized by self-respect of people with different opinions and of the environment."
Nudism is a synonymous to the "naturism" and is older term for it. Currently Nudism is principally used in North America. Unfortunately the term nudism is considered the relation with sexuality by the ignorant people those who don't know the advantage of the lifestyle.
Nudist is one who practices nudism, above all, they like to go naked, in any social naked activities and communal settings such as local club or resort. In my opinion, "nudist" is a one sect of naturists who especially like go naked as in above mentioned. Naturist is a one who practice nudism, feel closeness to the nature and environment. Respect the human rights, body, smoking, drinking, food and recycling etc... all the environment. Naturist rather tend to confirm of their activity for the pursuit of the clothing optional lifestyle.
Note: You should not confuse "naturism" with the term "naturalism". "Naturalism" is a doctrine which studies nature and no relation between two terms.
Some of nudists would not like to have the nudist philosophy. One should not always require the philosophical acquaintance to stay on the free beach.