RAG Step by Step

14 min read

A model does not know your college rules or today's news. RAG lets it read the right pages of your documents before it answers. In this lesson you follow one question through the whole pipeline.

New words

RAG
Retrieval-Augmented Generation: find useful text first, then let the model answer from it.
Indexing
Preparing your documents once so they can be searched fast.
Retrieval
Finding the chunks that are closest in meaning to the question.
Top-k
The k best-matching chunks. For example, top 3 means the best 3.
Hallucination
A confident answer from the model that is false or made up.
Citation
A note that tells the reader which source the answer came from.

What you will learn

  1. The problem: the model has not read your documents
  2. Two phases: indexing and answering
  3. Phase 1 in detail: build the index
  4. Phase 2 in detail: answer a question
  5. Try it: follow one question
  6. RAG or fine-tuning?
  7. Common failures
  8. In a real system
  9. Interview tip
  10. Key takeaways

10 quiz questions at the end.

Start this lesson

The full lesson, with interactive demos and the quiz, opens after you sign in with Google. It is free.

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