The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- Library works by Marx (0 members)
- Library works by Maxim Gorky (2 members)
- Library works by Michael Parenti (30 members)
- Library works by Moissaye Joseph Olgin (1 member)
- Library works by Muammar Gaddafi (3 members)
- Library works by Nia Frome (9 members)
- Library works by Nick Estes (2 members)
- Library works by Nicolo Machiavelli (1 member)
- Library works by Phil Ochs (18 members)
- Library works by Progress Publishers (1 member)
- Library works by Richard Levins (1 member)
- Library works by Richard Lewontin (1 member)
- Library works by Rosa Luxemburg (2 members)
- Library works by Samir Amin (1 member)
- Library works by Stalin (0 members)
- Library works by Sun Tzu (1 member)
- Library works by Sven-Eric Holmström (1 member)
- Library works by Thomas Paine (1 member)
- Library works by Thomas Sankara (2 members)
- Library works by Vijay Prashad (3 members)
- Library works by Vladimir L. Bobrov (1 member)
- Library works by Vladimir Lenin (31 members)
- Library works by W. P. Coates (1 member)
- Library works by Walter Rodney (1 member)
- Library works by Washington Huaracha Apaza (1 member)
- Library works by William Blum (1 member)
- Library works by William Z. Foster (4 members)
- Library works by Xi Jinping (5 members)
- Library works by Zelda Coates (1 member)
- Library works by Zhou Enlai (2 members)
- Library works by author (33 members)
- Library works by non-marxists and other authors (10 members)
- Library works from Albania (0 members)
- Library works from Brazil (0 members)
- Library works from China (0 members)
- Library works from Vietnam (0 members)
- Library works from the Soviet Union (0 members)
- Library works to be fact checked (0 members)
- Line charts (16 members)
- Line graphs (0 members)
- Literacy (1 member)
- Literary criticism (1 member)
- Literature (1 member)
- Lloyd family of Maryland (1 member)
- Locator maps (1 member)
- Logos (2 members)
- Logos of companies (1 member)
- Logos of political parties (1 member)
- Lyrics to songs by Phil Ochs (0 members)
- Lyrics to union songs (2 members)