GPT-4 is OpenAI‘s current state-of-the-art GPT-class model and the one which powers ChatGPT at time of writing.
GPT-4 is able to perform well at a large number of tasks including medicine and legal use cases. There is disagreement within the scientific community about whether this represents an ability to generalise or whether GPT-4 is so large and trained on so many documents that it simply memorises information from many domains.
GPT-4V
In late 2023, OpenAI rolled out multi-modal processing capabilities for GPT4, enabling it to process images and text at the same time. This makes GPT4 an Large Multi-Modal Model class model.