Glossary
Large Language Model (LLM)
The underlying AI model that powers AI engines: examples include GPT-5.6, Gemini 3.8, Claude Sonnet 5.5, and Grok 4.7.
Definition
An LLM is a neural network trained on massive amounts of text that can generate coherent responses to natural-language prompts. LLMs are the engines beneath the engines: ChatGPT, Claude, Perplexity, Gemini, and Grok are all products built on top of one or more LLMs. Different LLMs have different training data, different knowledge cutoffs, and different recommendation behaviors, which is why your visibility can vary engine-to-engine.
Example
ChatGPT runs on OpenAI's GPT family. Claude is Anthropic's LLM. Perplexity uses a mix including its own and others. Grok is xAI's model.
Related terms
AI Engine
A general term for the AI assistants and answer products that synthesize responses from multiple sources: ChatGPT, Gemini, Claude, Perplexity, Grok, Google AI Overviews and Google AI Mode.
Generative Engine
An AI system that generates answers (rather than retrieving them), typically powered by an LLM.
Hallucination
When an AI engine states something confidently that is factually wrong, including incorrect details about your brand.
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