AI visibility is how often — and how accurately — a brand is surfaced, described, and cited when people get answers from AI systems such as ChatGPT, Perplexity, Google’s AI Overviews, and Gemini. Optimising for it is called Generative Engine Optimization (GEO), a term introduced by Aggarwal and colleagues in their 2024 study at the ACM SIGKDD conference, which was the first to show that content can be deliberately optimised to be cited by generative engines. It is the subject of PhDr. Oliver Scharfenberg’s book The AI Visibility Playbook. GEO is closely related to what some call AEO, answer engine optimization.