Large language model
Also known as: LLM
A large language model is an AI system trained on very large amounts of text to understand and generate human-like language.
Short answer
A large language model (LLM) is an AI system trained on very large amounts of text to understand and generate human-like language. ChatGPT, Claude, and Gemini are all built on LLMs.
- Applies to:
- Anyone using ChatGPT, Claude, Gemini, or similar AI tools.
- Keep in mind:
- An LLM predicts likely text, so it can sound confident while being wrong. Verify facts before relying on them.
In more detail
An LLM learns patterns from a large body of text and uses them to predict the next piece of text given what came before. Tools like ChatGPT, Claude, and Gemini are built on LLMs. Because they predict likely text rather than looking up facts, they are excellent at drafting, rewriting, summarizing, and explaining — but they can also state wrong things confidently, so their output is a draft to review, not a source of truth.
Example
When you type "Rewrite this email to sound more polite" into ChatGPT, an LLM reads your email and generates a more polite version word by word, based on patterns it learned during training.
Why it matters
Understanding that an LLM predicts language (rather than knowing facts) explains both what it is great at — phrasing, structure, summarizing — and why you must check anything factual it tells you.
Prompts that use this
Sources
- 1.Large language model — Wikipedia
Wikipedia · verified 2026-07-26
Supports: Definition of a large language model as a model trained on large text corpora to generate language.
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