Artificial Intelligence

What is Hallucination?

Quick answer

When an AI model produces information that sounds plausible but is false, fabricated, or not supported by its source material.

Hallucination, explained

Language models generate text by predicting likely sequences of words. They do not check facts against a database by default, so they can confidently invent details: a nonexistent research paper, an incorrect date, a fake legal citation, or a quote nobody said.

Hallucinations are a key reason AI output needs human review, especially in medicine, law, finance, and journalism. Techniques that reduce, but do not eliminate, hallucinations include retrieval-augmented generation, which grounds answers in supplied documents, asking the model to cite sources, lowering randomness settings, and evaluating outputs automatically. Some researchers prefer the term confabulation. For bloggers using AI tools, the safest habit is to verify every factual claim before publishing.

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