Semigroups and Monoids
- Semigroup
- Subsemigroup
- Free semigroup
- Green's relations
- Inversion semigroup (cf. )
- Krohn–Rhodes theory
- Semigroup algebra
- Transformation semigroup
- Monoid
- Aperiodic monoid
- Monoid (category theory)
Read more about this topic: List Of Abstract Algebra Topics