2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/131641A little general abstract combinatorial nonsense delivered in this note is a presentation of some old and basic concepts, central to discrete mathematics, in terms of new words. The treatment is from a structural and systematic point of view. This note consists essentially of definitions and summaries.20 pagesCategory Theory05C99; 18B99text