2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/70093This paper is an introduction to a series of papers in which we give combinatorial models for certain important operads (including A-infinity and E-infinity operads, the little n-cubes operads, and the framed little disks operad) and combinatorial conditions for them to act on a given space or chain complex. The paper does not assume any prior knowledge of operads--Sections 2, 6 and 9, which can be read independently, are an introduction to the theory of operads.Quantum AlgebraAlgebraic Topology18D50; 55P48text