Homomorphisms are structure-preserving mappings between different types (called “category” in the post, in usual terminology, these would be »objects« in a »ca

Homomorphisms are structure-preserving mappings between different types (called “category” in the post, in usual terminology, these would be »objects« in a »category«, though). Endomorphisms are special homomorphisms, mapping from a single type (»object«) to the same type (»object«). It is indeed very unfortunate that the article conflates terminology.