The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- Roel Loopers (1 member)
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- Rosie O'Gradys (2 members)
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- Rowan Atkinson (1 member)
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- STV (2 members)
- San Francisco (1 member)
- Satish Kumar (2 members)
- Saving (2 members)
- Saw horses (1 member)
- Saw stools (1 member)
- Sawdust (1 member)
- Sawing (5 members)
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- Scenery (1 member)
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- Schema (1 member)
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- Scott Hanselman (2 members)
- Scripts (3 members)
- Searching (1 member)
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- SemanticForms (2 members)
- SemanticMediaWiki (1 member)
- Semantic MediaWiki (7 members)
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- Sessions (1 member)
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- Sharpening (1 member)
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- Societies (2 members)