The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- Soetsu Yanagi (1 member)
- Software (16 members)
- Software engineering (1 member)
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- Stack Overflow (2 members)
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- Suburbia (2 members)
- Subversion (4 members)
- Surveillance (1 member)
- Surveys (4 members)
- Susan Cain (1 member)
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- Swan River (1 member)
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- System administration (7 members)
- Systems (1 member)
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