> ## Documentation Index
> Fetch the complete documentation index at: https://wiki.platelunchcollective.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Large Language Model (LLM)

> A large language model (LLM) is a type of AI model trained on vast text corpora to understand and generate natural language.

*Core concept* · *AI Search Infrastructure*

## Definition

A large language model (LLM) is a type of AI model trained on vast text corpora to understand and generate natural language. LLMs power AI search tools such as ChatGPT, Claude, and Gemini — processing queries, retrieving content, and synthesizing responses at scale.

## Why It Matters for AI Search

LLMs are the engines of AI search. Understanding how they work — training data, weights, retrieval, context windows — explains why AI SEO behaves differently from traditional SEO. A brand that understands LLM architecture can make better decisions about where to invest: training corpus presence for parametric knowledge, [structured data](https://www.platelunchcollective.com/services/entity-seo) for retrieval accuracy, and content structure for context window extraction.

## Related Terms

<CardGroup cols={2}>
  <Card title="Foundation model" href="/ai-search-glossary/foundation-model" />

  <Card title="Training corpus" href="/ai-search-glossary/training-corpus" />

  <Card title="RAG" href="/ai-search-glossary/rag" />

  <Card title="Inference" href="/ai-search-glossary/inference" />

  <Card title="Pre-training" href="/ai-search-glossary/pre-training" />
</CardGroup>

## Relevant Plate Lunch Collective Services

[AI SEO](https://www.platelunchcollective.com/services/ai-seo)  [AI Search Visibility Assessment](https://www.platelunchcollective.com/services/context-map)