Vectorize is Cloudflare's vector database. AI Search is the right starting point for a managed RAG pipeline; Vectorize is the better fit when you need control over chunking, embeddings, metadata filters, hybrid retrieval, reindexing, and fallback behavior.
Week 5's public materials support the distributional hypothesis, word embeddings, and cosine similarity; the paired Social NLP lecture is unrecorded and restricted, so concrete audit methods are labeled as author extensions.
Lecture 2 moves from word2vec's prediction task, objective, and gradients to count-based vectors and evaluation. Meaning becomes a high-dimensional position learned from context, not a label retrieved from a dictionary.