2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/61294The concept of n-categories and related subject is considered. An n-category is described as an n-graph with a composition. A new definition of operad is presented. Some illustrative examples are given.12 pages in Latex. Submitted to `Miscellanea Algebraica', Waldemar Korczyński and Adam Obtułowicz, Editors, Akademia Świ{ȩ}tokrzyska, Kielce, PolandCategory Theorytext