[[!redirects 1. an overview of higher category theory]] This is a subentry of [[a reading guide to HTT]]. ###1.1 Foundations for higher category theory $\infty$-categories as simplicial sets $\infty$-categories as categories enriched in 1. $sSet$ 1. $Top_CG$ ### 1.2 The language of higher category theory [[1.2 basic infinity-category theory]]