Memory vs. Context Window vs. RAG: What's the Difference?

The context window is where the model works right now — fast, immediate, temporary, and bounded. It's the agent's working memory, nothing more. RAG is how relevant information gets fetched into that window — a retrieval technique. Memory is the persistent state that outlives the session. Memory uses RAG to retrieve, and always lands in the context window — but it's the same as neither. Three words, constantly confused Memory, context, and RAG get used almost interchangeably, and that…