What is ChatGPT? — AI Glossary

What it is: ChatGPT is an AI chatbot made by OpenAI. It’s the most-used AI assistant in the world.
Who it’s for: Beginners who keep hearing the word “ChatGPT” and want a plain-English explanation.
Best if: You want a one-page primer before deciding whether to try it.
Skip if: You already use ChatGPT daily — go to our How to Use ChatGPT guide instead.

ChatGPT is an AI assistant from a company called OpenAI. You type a question or a request in plain English, and it answers in plain English. You can ask it to write, summarize, explain, brainstorm, plan, code, translate, or analyze almost anything. The full name comes from the model family that powers it — GPT, short for Generative Pre-trained Transformer — combined with “chat.”

OpenAI launched ChatGPT publicly on November 30, 2022. It crossed 100 million users within two months, the fastest-growing consumer application in internet history at the time. By mid-2026, ChatGPT serves more than 700 million weekly users worldwide and remains the single most-used AI product on the planet.

What ChatGPT can do

• Write and edit: emails, essays, reports, marketing copy, code, scripts, summaries.
• Answer questions: from general knowledge to specific technical topics.
• Analyze documents and images: upload a PDF, screenshot, or photo and ask questions about it.
• Generate images: through the built-in DALL-E feature on paid tiers.
• Search the live web: for current events, prices, and news.
• Speak and listen: Voice Mode lets you have a spoken conversation through the mobile or desktop app.
• Take actions on your behalf: through agentic features like ChatGPT Operator and the Atlas browser.

How to use ChatGPT

• Free: Sign up at chatgpt.com. The free tier is generous enough to evaluate whether ChatGPT fits how you work.
• Paid (ChatGPT Plus, $20/month): higher usage limits, the latest models, faster responses, image generation, voice features.
• ChatGPT Pro ($200/month): heavy usage with extended limits, used by professional writers, researchers, and developers.
• Team and Enterprise: shared workspaces, admin controls, data-privacy guarantees. See our ChatGPT plans compared.
• Mobile and desktop: native apps on iOS, Android, macOS, and Windows.

What ChatGPT is not

ChatGPT is not a search engine, though it can search the web. It is not a database of facts — it generates language based on patterns learned during training, which means it can hallucinate — produce confident-sounding but incorrect information. For anything that matters (medical, legal, financial, factual), always verify against authoritative sources. ChatGPT is also not the only good AI chatbot — Claude and Gemini are direct competitors with their own strengths.

Related terms: OpenAI, Chatbot, Large Language Model (LLM), Prompt, Custom GPTs, AI Hallucination, Context Window.

Learn more: How to Use ChatGPT: Complete Beginner’s Guide (2026), ChatGPT Plus vs Pro vs Free, What’s New in ChatGPT 2026, ChatGPT vs Claude vs Gemini. Get every ChatGPT update as it ships in our free daily Beginners in AI newsletter.

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