AI GLOSSARY

What is Hallucination?

Hallucination
A. What is Hallucination
When an AI generates content that is factually wrong but sounds plausible. Always verify important information against primary sources.

A hallucination is when a generative AI outputs nonexistent facts, sources or figures as if they were correct. It can occur because of how LLMs work — they generate “the most probable next word.”

Countermeasures include using AI search that cites sources, retrieval-augmented generation (RAG), and asking the model in the prompt to provide its evidence. On this site, too, figures are based on public data with sources and capture dates clearly noted.

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Reference values based on public data and editorial research; not a complete count of actual users.