Definition
Perplexity is the most directly optimisable AI search surface: it retrieves live, cites every source, and updates within days. A correctly optimised page can appear in Perplexity citations within days of publishing. The Sonar API family lets developers embed Perplexity-style retrieval.
Why it matters
Perplexity sits in the "Surfaces & platforms" layer of the AI search stack. Teams that handle it well get cited more, recommended more, and earn more of the AI-mediated revenue in their category. Teams that ignore it spend a year wondering why their content investment never moves the needle inside ChatGPT or Perplexity.
Related terms
- PerplexityBot - Perplexity's live-retrieval crawler. Blocking it removes you from Perplexity citations.
- Citation share - Percentage of cited sources in an LLM answer that come from your domain. Only meaningful on grounded surfaces (Perplexity, ChatGPT Search, AI Overviews).
- AEO - Optimizing content so answer engines (Perplexity, Google AI Overviews, ChatGPT Search) quote it as the direct answer to a query.
- RAG - A technique where an LLM retrieves external documents at inference time and uses them to ground its answer. Powers Perplexity, ChatGPT Search, and AI Overviews.
Apply it
The LLM SEO playbook ties every concept in this glossary into a single operating model. If you want to see how your brand performs across all the LLMs at once - mention rate, citation share, sentiment, rank - start with the free GEO audit or skip straight to a free Livesov account.