Naturism or nudism is a cultural and political movement advocating and defending social nudity in private and in public. It may also refer to a lifestyle based on personal, family and/or social nudism. 
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A nudist community (nudist colony) is a group of nudists/naturists who choose to live together on a permanent basis whilst avoiding wearing clothes; 
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Nude swimming (colloquially called skinny dipping, also known as skin diving) is a term used to describe swimming naked, i.e. without any swimsuit. 
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