The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.

• MNET (1 member)
• MNet (10 members)
• Mac OS X (5 members)
• Mathematics (36 members)
• Medicine (8 members)
• Messaging (20 members)
• Mobile (28 members)
• Modules (2 members)
• Moodle.org (3 members)
• Moodle.org improvements (9 members)
• Moodle23 (1 member)
• MoodleDocs (26 members)
• MoodleDocs administration (2 members)
• MoodleNet (0 members)
• MoodleTxt (19 members)
• Moodle 1.7 (3 members)
• Moodle 1.8 (2 members)
• Moodle 1.9 (13 members)
• Moodle 2.0 (70 members)
• Moodle 2.1 (1 member)
• Moodle Docs (1 member)
• Moodle For Mobiles (1 member)
• Moodle User Interface Guidelines (17 members)
• Moodle an Hochschulen e.V. (1 member)
• Moodleposium (1 member)
• Moodleposium/2010 (1 member)
• Moved to dev docs (14 members)
• Multimedia (18 members)
• Music (6 members)
• New features (40 members)
• Notes (4 members)
• OAuth 2 (15 members)
• Obsolete (2 members)
• Open University (11 members)
• Output (1 member)
• Page (3 members)
• Pages for deletion (4 members)
• Pages needing improvement (3 members)
• Pages requiring a review (2 members)
• Pages requiring updating (15 members)
• Pages that use a deprecated format of the math tags (2 members)
• Pages using deprecated source tags (1 member)
• Pages with broken file links (36 members)
• Pages with ignored display titles (10 members)
• Pages with syntax highlighting errors (3 members)
• Pages with too many expensive parser function calls (1 member)
• Pedagogy (2 members)
• Performance (16 members)
• Physics (3 members)
• Plagiarism prevention (17 members)