Claude is a conversational AI assistant built by Anthropic, leveraging Constitutional AI—a unique training method that embeds ethical principles into its responses to ensure helpfulness, honesty and harmlessness [tomsguide.com]. It supports multimodal input, including text and images, and boasts a massive context window—up to 200,000 tokens for most users and 1 million tokens in enterprise applications—making it particularly adept at analyzing lengthy documents and complex workflows [tomsguide.com]. Claude’s model family ranges from fast, affordable versions (Haiku) to the powerful Opus variants, with the latest Claude 4 Opus having demonstrated autonomous code generation for up to seven hours straight [reuters.com]. The current flagship is Claude 3.7 Sonnet, a hybrid‑reasoning model allowing users to choose between speedy answers or in‑depth, step‑by‑step logic [reuters.com]. Finally, it’s available via web, desktop, mobile apps, and API, with flexible tiers—including free, Pro, Team, and Enterprise plans—making it accessible across personal and professional use cases [tomsguide.com].