What is Claude AI?
Claude is an AI assistant made by Anthropic, a safety-focused AI company founded in 2021. It's a large language model you chat with at claude.ai to write, code, analyze documents, and answer questions. Named after information theory pioneer Claude Shannon, it comes in a tiered lineup (Haiku, Sonnet, Opus, and the flagship Fable) with free and paid plans.
Why — the first-principles explanation
At bottom, Claude is a large language model (LLM): a program trained on huge amounts of text that answers by predicting the most likely next chunk of words. What makes it 'Claude' rather than any LLM is who built it and how. Anthropic is an AI safety company started in 2021 by former OpenAI researchers, and it trains Claude with a method called Constitutional AI, a written set of principles the model uses to keep its answers helpful, honest, and harmless.
You meet Claude as a chat assistant at claude.ai (web, desktop, and mobile) and, for developers, as an API. Under the hood it's not one model but a family tuned for different needs: Haiku for speed, Sonnet for balance, Opus for deep capability, and Fable as the flagship for the hardest, long-running work. All current models are multimodal (they read text and images) and current top models hold up to a 1M-token context window.
The practical point is that Claude turns a research breakthrough into an everyday tool. You type a request in plain language, and Claude drafts an email, writes code, summarizes a report, or explains a photo. It's free to start, with paid Pro and Max plans for heavier use, and it's designed so its safety and honesty aren't bolt-ons but part of how it was trained.
An example that makes it click
Imagine a brilliant, well-read intern who has read most of the public internet and can write, code, and summarize on demand, but who was also given a strict code of conduct so they stay honest and refuse harmful tasks. You talk to this intern through a chat box. That intern is Claude, and the company that trained and coaches it is Anthropic.
Key facts
- Claude is an AI assistant (large language model) built by Anthropic, founded in 2021.
- It is named after Claude Shannon, the founder of information theory.
- Anthropic trains Claude with Constitutional AI to be helpful, honest, and harmless.
- The lineup includes Haiku (fast), Sonnet (balanced), Opus (capable), and Fable 5 (flagship).
- You access it free at claude.ai, with Pro ($20/month) and Max (from $100/month) paid plans.
Anthropic's assistant, known for long-document reasoning and careful, safe answers.
Affiliate link — we may earn a commission at no cost to you.▶ The 60-second explainer (script)
What is Claude AI? Claude is an AI assistant built by Anthropic, a company founded in 2021 that focuses on making AI safe. Technically, Claude is a large language model, a program trained on enormous amounts of text that answers by predicting the best next words. You chat with it at claude.ai to write, code, analyze documents, and answer questions in plain language. It's named after Claude Shannon, the father of information theory, and it's trained with a method called Constitutional AI, which gives it a written set of principles to stay helpful and honest. Claude isn't a single model but a family: Haiku is fast, Sonnet is balanced, Opus is powerful, and Fable 5 is the flagship for the hardest tasks. It's free to start, with paid plans for heavier use.
What authoritative sources say
People also ask
Who makes Claude?
Anthropic, an AI safety company founded in 2021 by former OpenAI researchers.
Why is it called Claude?
It is widely understood to be named after Claude Shannon, the mathematician who founded information theory.
Is Claude the same as ChatGPT?
No. Both are AI chat assistants, but Claude is made by Anthropic and ChatGPT by OpenAI, with different models and features.
How do I try Claude?
Go to claude.ai and sign up free with an email or Google account; paid Pro and Max plans add higher usage.