Introductory informative
The Concepts section of KERIDoc: a concepts page, a mind map, a roadmap, insights into the KERI development toolbox, a contributors' guide, and a set of how-to pages (set up a basic KERI network, make a schema, issue, present and verify a credential, build an ACDC graph), several of them still stubs.
Found through KERISSE, the KERI Suite Search Engine (Kor Dwarshuis and Henk van Cann), whose dataset is the source of the documents the base indexes.