OpenAI models: Every model (including GPT-5.6) and what it's best for

Keeping track of all the new AI models getting released at the moment is practically a full-time job. The most recent model, GPT-5.6, was released less than three months after GPT 5.5, which itself was released two months after GPT-5.4. I've been writing about OpenAI's models for the past few years, and it feels like every time I publish an article, another new model drops. OpenAI is one of the worst offenders (or prolific innovators), and things aren't helped by how confusing all the OpenAI mod