ภาพรวมสถาปัตยกรรมระบบ RAG เบื้องต้น

Now let's look at the building blocks of a RAG system. Knowing the architecture shows you exactly how RAG makes LLMs more accurate and reliable.

RAG blends retrieval (finding info) and generation (creating text) through three components: data sources, a retriever, and a generator.

The data sources hold the external knowledge your LLM wasn't trained on — PDFs, web pages, internal wikis, database records, and more.

First your data gets processed: large documents are split into smaller, searchable pieces called chunks, like indexing a library by chapter instead of by whole book.

The retriever is a smart search engine for your chunks. It understands the meaning of a query, not just keywords, to fetch the most relevant context.

When a user asks, the retriever scans all processed chunks and pulls out the few most likely to hold the answer, passing them along as context.

The generator is your LLM — the part that writes the response. In RAG it gets two inputs: your original question and the context the retriever found.

Instead of leaning on pre-trained knowledge alone, the LLM uses retrieved context to ground its answer, like an expert handed the exact reference documents.

The full RAG flow: query in, retriever finds chunks, query plus chunks go to the generator, the LLM writes a grounded answer, the user gets a factual reply.

Which component is primarily responsible for finding relevant information from your knowledge base when a user asks a question?

Recap: a RAG system has three parts — data sources (the knowledge), retriever (the smart search), and generator (the LLM crafting grounded answers).