GPT-4o and GPT-4o mini are the latest multimodal AI models from OpenAI, offering faster speeds and lower costs compared to their predecessors, while maintaining or surpassing performance on various benchmarks. These models can process text, audio, and images simultaneously, enabling ChatGPT users to ask questions with voice input, receive responses in both text and image formats, and even interrupt the model mid-conversation. The GPT-4o models work similarly to other GPT models but were trained on a broader range of data sources, including images and audio. They utilize the transformer architecture and have been fine-tuned for safety and usability. While the models show promise in providing a more practical and useful experience, they still struggle with confidence and accuracy in certain situations, such as parsing handwriting or solving complex puzzles. GPT-4o mini is positioned as a cost-effective option for developers, while both models are available through an API for commercial use.