What is RAG? Giving AI Access to Your Business Data

You've probably used ChatGPT or Gemini and noticed something: it's knowledgeable about the world, but it doesn't know anything about your business. It doesn't know your products, your customers, your policies, your processes. This is the gap that RAG fills.

The knowledge cutoff problem

Large language models like GPT-4 and Gemini are trained on data up to a certain date. They don't know what happened in your company last week, last month, or ever — unless you specifically give them that information. And even then, you can't retrain the model every time you want to update its knowledge.

RAG is a technique that solves this by giving the AI a way to look up relevant information at the time of the query, before generating its response.

How RAG works

Here's the simple version: your documents (PDFs, emails, databases, knowledge base articles) are processed and stored in a vector database. When a user asks a question, the system searches the vector database for documents relevant to that question, retrieves them, and includes them in the AI's context window. The AI then answers the question using both its general knowledge and your specific documents.

Imagine an AI customer support agent that has access to your entire product manual, return policy, and past support tickets. When a customer asks about a specific problem, it retrieves the relevant section of the manual and combines it with examples of how similar issues were resolved. That's RAG in action.

Why RAG matters for your business

Without RAG, you can only use AI with information it was trained on. With RAG, you can build AI systems that know everything your organisation knows — in real time, with documents you update as your business changes. The AI isn't a generic assistant; it's an expert on your specific context.

The practical applications are immediate: AI support agents that know your products, internal search that understands your documents, AI writing tools that use your brand voice and guidelines. RAG is the unlock that makes AI genuinely useful, not just interesting.