WHAT IT IS
Claude is Anthropic’s conversation-model family, first released in March 2023. Anthropic was founded by former OpenAI researchers and centres its methods on “Constitutional AI”: a written set of principles guides the model to critique and revise its own outputs, reducing reliance on human labelling. The Claude family is widely adopted for long-context handling and steady performance on text and code tasks. It is available through the API and claude.ai, alongside tools such as the coding-oriented Claude Code.
Why it matters
It turned “let the model critique and revise itself against a written set of principles” — Constitutional AI — into a scalable alignment method, and was among the early drivers of long-context conversational models.
Key specs
- Context window
- 200K tokens
- Modality
- Text, image in; text out
- Alignment
- Constitutional AI
- Released
- 2023-03
Capabilities
Conversation & Instruction Following
Understand intent across turns and act on it
Text Generation
Continue a passage, one word at a time
Reasoning & Chain-of-Thought
Break a hard problem into intermediate steps
Code Generation
Write runnable code straight from a description
Related concepts
Transformer Architecture
Replacing word-by-word relay with a room where everyone speaks at once, so long-range dependencies are one hop away
Prompting & Alignment
Making a model helpful, honest and harmless is harder than simply making it bigger
Reinforcement Learning from Human Feedback
When the good answer cannot be written as a formula, let humans stand in as the reward function
Comparable products
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Llama
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Grok
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Gemini
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Microsoft Copilot
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Character.AI
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