LLM SEO is the practice of making a brand's content easy for large language models to find, understand and cite when they answer questions, in tools such as ChatGPT, Gemini, Perplexity and Copilot.
The term is often used interchangeably with generative engine optimisation. In practice it covers the same work: allowing AI search crawlers, getting key pages indexed in Bing and Google, writing passages that answer directly and name the brand, keeping entity data consistent, and earning mentions in the third-party sources language models draw on.