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AI Glossary

What is AI Hallucination?

When an AI generates false or fabricated information that sounds plausible.

By Council Research TeamUpdated: Jan 27, 2026

Definition

AI hallucination occurs when a language model generates content that is factually incorrect, nonsensical, or completely fabricated, but presents it confidently as if it were true. This happens because LLMs are trained to predict likely text, not verify facts.

Examples

1Citing non-existent research papers
2Inventing fake statistics
3Creating fictional quotes attributed to real people

Why It Matters

Understanding hallucinations helps you verify AI outputs and use tools like Perplexity that provide citations.

Related Terms

Large Language Model (LLM)

An AI system trained on vast text data to understand and generate human-like text.

Grounding (AI)

Connecting AI responses to verifiable facts and real-world data sources.

RAG (Retrieval-Augmented Generation)

Combining AI with real-time information retrieval from external knowledge bases.

Common Questions

What does AI Hallucination mean in simple terms?

When an AI generates false or fabricated information that sounds plausible.

Why is AI Hallucination important for AI users?

Understanding hallucinations helps you verify AI outputs and use tools like Perplexity that provide citations.

How does AI Hallucination relate to AI chatbots like ChatGPT?

AI Hallucination is a fundamental concept in how AI assistants like ChatGPT, Claude, and Gemini work. For example: Citing non-existent research papers Understanding this helps you use AI tools more effectively.

Related Use Cases

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AI Models Using This Concept

ClaudeClaudeChatGPTChatGPTGeminiGemini

See AI Hallucination in Action

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