Definition
People Also Ask is the expandable Q&A section on Google SERPs showing 4+ related questions other users searched. Powered by the same retrieval system that drives featured snippets + AI Overviews. The questions reveal sub-query intent and the answers reveal which pages Google trusts as authoritative on each angle.
Search 'AEO' → PAA shows 'What is AEO?', 'How is AEO different from SEO?', 'Which engines use AEO?' These are the sub-queries Google has decomposed.
How to optimize
Mine PAA for your seed queries. Answer each PAA question on your page with a dedicated H2 + 50-word answer. Watch for new PAA questions appearing: they signal evolving intent.