The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- Supporters (1 member)
- Symposia (2 members)
- Systems Science Organizations (4 members)
- T/Events (5 members)
- T/Media (6 members)
- T/Organizations (1 member)
- T/Other (3 members)
- T/People (10 members)
- T/Projects (6 members)
- T/Reports (5 members)
- T/Resources (1 member)
- T/Software (1 member)
- T/Talented Youth (0 members)
- TV Promotion (4 members)
- Talented Youth (0 members)
- TeachMDGs Conferences (1 member)
- TeachMDGs in Newspapers (1 member)
- Tech4Peace Events (1 member)
- Telsim-Cyberethics Events (20 members)
- Template Images (4 members)
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- Tenders (1 member)
- Trainings (4 members)
- Turkish (1 member)
- Turkish Cypriots (7 members)
- UNDP Projects (6 members)
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- URVT Trainings (2 members)
- US-funded Projects (5 members)
- USAID Projects (1 member)
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- Upcoming interns (2 members)
- Video Conferences (2 members)
- Visiting Scientists (14 members)
- Vitae (16 members)
- Vitae/Aleco Christakis (7 members)
- Vitae/Chrystalla Miltiadou (4 members)
- Vitae/Inga Wojcik (3 members)
- Vitae/Kevin Dye (4 members)
- Vitae/Pier-Luigi Emiliani (1 member)
- Vitae/Pier Luigi Emiliani (2 members)
- Vitae/Serge Gawbene Buthendw (5 members)
- Vitae/Yiannis Laouris (15 members)
- Volunteers (3 members)
- Wittig Awards (3 members)
- Workshops (3 members)
- Y2P Events (37 members)
- YIA Projects (12 members)
- Youth-related Projects (5 members)
- Youth Promoting Peace (1 member)