Perplexity
Also called: Perplexity AI
Perplexity is an AI answer engine that searches the live web and replies with a synthesized, conversational answer plus numbered inline citations to the sources it used, instead of returning a ranked list of links like a traditional search engine.
How Perplexity builds an answer
Under the hood Perplexity runs retrieval-augmented generation (RAG). For each question it parses the query, pulls candidate pages from its own index and the live web, ranks them, then feeds the top passages to a language model that writes the reply. The citations are not bolted on afterward. Perplexity assigns them while it assembles the prompt, which is why every claim carries a clickable [1], [2] marker that lands on the exact page a sentence came from.
Two crawlers feed this. PerplexityBot is the indexing crawler, and Perplexity’s own docs say it is “designed to surface and link websites in search results on Perplexity” and that webmasters should allow it in robots.txt. Perplexity-User fetches a page in real time when a user’s question needs it, and the docs note it “generally ignores robots.txt rules” because it acts on an explicit request. Block PerplexityBot and you opt out of being indexed as a citable source.
Perplexity launched in 2022, co-founded by Aravind Srinivas (previously a research scientist at OpenAI). It sits in the same answer-engine category as ChatGPT search and Google’s AI Overviews, but its always-visible numbered citations make it the clearest place to watch which sources an AI actually rewarded and which it passed over.
How it affects your traffic
Perplexity fetches many candidate pages per query but cites only a handful, and the outcome is binary: you are either the cited source or invisible, with no page-two consolation prize. The win is not a ranking position, it is being the passage the model quotes, which rewards front-loaded answers, fresh content, clean structured data, and genuine topical depth over raw domain size. Earning that citation, and tracking whether you actually get it, is the core of our AI SEO work.
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