Definition
Answer Engine
An answer engine is an AI system that responds to a question with a direct, synthesized answer, often citing sources, instead of returning a list of links. ChatGPT, Gemini, Perplexity and Google's AI Overviews are answer engines.
Because the output is a short answer naming only a few sources, being one of those cited sources is the whole game, which is what AEO optimizes for.
What are examples of answer engines?
ChatGPT, Google Gemini, Perplexity and Google's AI Overviews are all answer engines, they synthesize a direct answer to a query rather than only listing links.