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Language models

Hallucination

Level 1

When a model states something false with complete confidence.

Term 6 of 8 in Language models

In plain language

Because a model is predicting plausible text rather than retrieving verified facts, it can invent a citation, a date or a quote that simply does not exist. It has no internal signal that it is guessing.

Think of it like this

Like a very well-read person who would rather give a confident answer than admit they cannot remember.

Why it matters

Hallucination is the single most important reason to verify AI output before you act on it.

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