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What Is RAG? A Plain-English Explainer

What Is RAG? A Plain-English Explainer

AI Glossary

A plain-English explainer on Retrieval-Augmented Generation, how it works, and why it matters more than context window size for accuracy against your own data.

RAG shows up constantly in AI product descriptions, and it solves a genuinely specific problem: getting a model to answer using your actual, current data instead of only what it learned during training.

Retrieval-Augmented Generation works in two steps. First, retrieve the specific, relevant pieces of information from your own documents or database. Second, feed those retrieved pieces to the model alongside the question, so it answers based on your actual data rather than guessing from training data alone.

Our explainer on context windows covers why simply pasting your entire knowledge base into a huge context window tends to underperform a well-designed retrieval system pulling only the relevant sections first. RAG is that retrieval layer.

Internal company chatbots answering questions from private documentation, customer support tools referencing real product documentation, any application needing answers that reflect current, proprietary information, these are the classic use cases.

RAG is the difference between a model guessing from general training and one referencing your specific, current information. See a broader technical overview for more depth.

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How to Summarize Long Documents With AI

How to Summarize Long Documents With AI

How-To

A practical guide to summarizing long documents with AI, covering audience specificity, context window limits, structure, and verification.

Summarizing a long document is one of the most reliable, lowest-risk AI use cases, and a few specific habits make the difference between a generic summary and one you can actually act on.

“Summarize this” produces a generic, middle-of-the-road summary. “Summarize this for someone deciding whether to approve the budget in it, lead with the number that matters most” gives the model a target to write toward, the same principle covered in our prompt engineering guide.

Very long documents can push against a model’s context window, and recall gets less reliable as stuffed context grows, even within the stated limit. For genuinely long documents, summarizing section by section and combining those summaries often beats a single pass.

A bulleted summary with key points, decisions, and action items separated out is usually more useful than a paragraph, especially if you need to scan it or share it with someone who won’t read the original.

For a summary you’re just using to decide whether to read the full thing, a quick pass is fine. For anything you’ll act on directly, spot-check the specific numbers and claims against the original first. See the International Fact-Checking Network for general verification standards.