AEO, short for Answer Engine Optimisation, is the discipline of shaping content so that AI systems such as ChatGPT, Gemini, Perplexity and Claude pull it into their generated answers and attribute it to your brand. That is a different goal from ranking on a results page. An answer engine reads a page, extracts the parts it trusts, and rewrites them into a conversational response, often without sending a single visitor to the source.
The traffic model underneath this has already shifted, which is why it matters to anyone holding a marketing budget. A prospect asking ChatGPT "what's the best expense management tool for a 50-person startup" never sees ten blue links. They see one synthesised answer, and whichever three or four brands get named become the shortlist. If your product is not one of the names, you are excluded before the buyer has visited a single website. AEO is how a brand earns a place in that shortlist, and budget owners are shifting spend toward it because organic search volume for commercial queries is flattening while assistant usage climbs.
The mechanics come down to structure: state the answer inside the first two sentences instead of building up to it, use headings that match how people actually phrase questions, add schema markup so facts are machine-readable, and swap vague claims for specifics such as pricing, dates and comparisons. Models favour content that reads as a fact they can quote without editing, so a paragraph full of marketing adjectives gets paraphrased or skipped, while a paragraph with a number, a name and a date gets copied almost verbatim.
A mid-market HR software company restructured its "applicant tracking system" comparison page: it moved the direct answer to the top, added a pricing table with named competitors, and marked up the FAQ section with schema. Before the change, the brand appeared in 9 of 100 tracked prompts across ChatGPT and Perplexity for buyer-intent queries in its category. Twelve weeks later, that figure rose to 31 of 100, and its Share of Voice against its four closest competitors went from 14% to 29%. No new backlinks were built and no new content volume was added; the only lever was making the existing page easier for a model to extract and cite.
AEO gets confused most often with GEO, Generative Engine Optimisation, and industry usage of the two terms genuinely has not settled, with plenty of practitioners using them interchangeably. Where a distinction is drawn, AEO is treated as the broader discipline: it covers earning citations and recommendations across any answer-style surface, from a single question-and-answer exchange to a voice assistant reply to a multi-source AI Overview. GEO is the newer, narrower label, reserved for tactics aimed specifically at generative synthesis models such as ChatGPT, Gemini and Perplexity that write a novel answer rather than retrieve one. Vendors and practitioners blur this line constantly, so when reading a report or a tool's marketing, check what is actually being measured rather than which label is used.