The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- Hull series (6 members)
- Human Characters (280 members)
- Human companies (252 members)
- Hunter images (3 members)
- Hurricane Images (73 members)
- Hurston (31 members)
- Hurston AO Missions (46 members)
- Hurston Dynamics (42 members)
- Hurston Dynmaics (1 member)
- Hurston FPS Cave Missions (2 members)
- Hurston Falimy images (1 member)
- Hurston Family images (4 members)
- Hurston family (14 members)
- Hurston images (76 members)
- Hyoton System (4 members)
- Hyper Vanguard Force IV images (5 members)
- Hyperion (1 member)
- Hyperion images (1 member)
- I18n templates (3 members)
- IMS-Bolliver (1 member)
- INS Jericho images (1 member)
- IR missiles (10 members)
- IR torpedoes (4 members)
- Ice Giant (17 members)
- Ice Planet (11 members)
- Icebreaker images (1 member)
- Idris-K images (3 members)
- Idris-M images (20 members)
- Idris-P images (1 member)
- Idris System (7 members)
- Idris images (1 member)
- Idris series (4 members)
- Illyana Sharrad images (1 member)
- Images (44 members)
- Images without source (31 members)
- Impact-S1 images (1 member)
- Imperator (1 member)
- Imperators (19 members)
- Imperial Cartography Center (1 member)
- In Area18 (3 members)
- In Area 18 (3 members)
- In Concept (1 member)
- In GrimHEX (3 members)
- In Levski (2 members)
- In Lore (1 member)
- In Lorville (10 members)
- In New Babbage (5 members)
- In Orison (12 members)
- In Production (1 member)
- In Ruin Station (1 member)