GPT-5, OpenAI's latest AI model, is highly advanced, offering improved performance, reasoning, and tool usage with capabilities extending to 400,000 tokens. It introduces features like multi-stage model routing, enhanced agentic behavior, and developer-oriented controls, making it suitable for complex tasks across multiple domains, including coding, healthcare, and multimodal understanding. The model family includes variants like GPT-5 Mini, Nano, and Pro, each optimized for specific use cases. GPT-5 is accessible via ChatGPT, OpenAI API, and Microsoft integrations, and it maintains compatibility with GPT-4 prompts. Alternatively, OpenAI's GPT-OSS models offer open weights for users seeking transparency and control, employing a Mixture-of-Experts architecture for efficient, scalable applications. These models are available for download under an Apache 2.0 license, supporting long-context applications and local deployments.