Retrieval-Augmented Generation explained in plain English. The librarian analogy, the five steps, a working Python example you can run in 50 lines, and the mistakes every beginner makes the first time.
Retrieval-augmented generation has been wrapped in enough mystique to obscure that it's mostly an ETL problem. What the pipeline actually looks like, where the real engineering happens, and the failure modes that have nothing to do with the model.