In more detail
A hallucination is when an AI states something false with complete confidence — a fake fact, a made-up quote, a book that doesn’t exist. It isn’t lying; it has no idea it’s wrong. Under the hood the model predicts what plausible text looks like, and sometimes plausible and true part ways.
This is the single most important habit to build with AI: treat it like a brilliant friend with a shaky memory. Wonderful for drafts, ideas and explanations — but verify names, numbers and citations before you rely on them anywhere that matters.
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