Naturism
Naturism (or nudism) is the lifestyle and philosophy of going nude — practicing non-sexual social nudity in private and in shared spaces like beaches, resorts, and clubs. At its core it's explicitly not about sex: the point is comfort, body acceptance, freedom, and a connection to nature without clothing. That said, some people find personal or erotic pleasure in nudity, which is where it can brush against exhibitionism or a nudity kink. It has organized communities, designated beaches, and clubs worldwide. It overlaps at the edges with exhibitionism and body freedom.
For most naturists the appeal is freedom and acceptance — the ease and honesty of being unclothed, comfort in one's own body, and a natural, non-judgmental connection with others and the outdoors. Where it is erotic for someone, it's the liberation and mild exposure of nudity itself.
People practice it by spending time nude — at home, on naturist beaches, at resorts or clubs, or in nature — socializing, swimming, and relaxing without clothes, following the community's non-sexual etiquette in shared spaces.
Low-risk. In communal naturist settings, respect the non-sexual norms and others' boundaries (no staring, photos, or overt arousal); for nude sunbathing, mind sunscreen. Public nudity outside designated areas can run into local decency laws.
Naturists are usually emphatic that the lifestyle is non-sexual — it's about body acceptance and comfort, not arousal — and dedicated naturist spaces enforce that norm. The erotic angle (nudity as a turn-on) is a separate, personal thing that naturist etiquette generally keeps out of communal settings.