A search engine hands you a ranked list and lets you choose. An answer engine reads for you and writes the reply: ChatGPT’s search features, AI summaries shown at the top of search results, and AI assistants built into browsers and apps all work this way.
For a buyer, that is convenient. For a brand, it changes the competition. When someone asks “which mattress is best for back pain?”, an answer engine doesn’t show twenty results; it names a few products and gives reasons. The brands on that short list are in the buyer’s consideration; the rest may never be seen in that moment.
Most answer engines that cover current products search the web while answering (see web search, or grounding), so the pages they can find and trust shape who gets named. Answers also vary from one ask to the next, which is why measuring an answer engine means asking the same question several times.
Citationly measures ChatGPT today: OpenAI’s model, asked through its API with web search on. Read how ChatGPT decides which brands to name.