Drazin inverses are a special kind of generalized inverse that have been extensively studied in ring theory, semigroup theory, and matrix theory. Drazin inverses can also be defined for endomorphisms in any category. In this talk I’ll give an introduction to Drazin inverses from a categorical perspective. Based on this paper: (link) which is joint work with Robin Cockett and Priyaa Varshinee Srinivasan