GPTGenerative Pre-trained Transformer — OpenAI's family of large language models from GPT-1 through GPT-5.-5.6 arrived after a limited government preview and regulatory clearance — OpenAIAn AI research company — created GPT, ChatGPT, DALL-E, and the o-series reasoning models.'s answer to Claude Cowork and the post-Fable agent wave. Sol targeted frontier reasoningStep-by-step logical thinking in AI models — chain-of-thought before answering hard problems., Terra balanced everyday work, and Luna cut cost — while ChatGPTOpenAI's conversational chat product — brought large language models to hundreds of millions of users. Work merged Codex into a desktop agent for non-coding office tasks.

GPTGenerative Pre-trained Transformer — OpenAI's family of large language models from GPT-1 through GPT-5.-5.6 paired a three-tier model family with OpenAIAn AI research company — created GPT, ChatGPT, DALL-E, and the o-series reasoning models.'s first general workplace agent.

ChatGPTOpenAI's conversational chat product — brought large language models to hundreds of millions of users. Work made Codex-class agents available for clerical work, not just code.