Canvas is the name of an extension that OpenAI has created specifically for developers.

Chat GPT was released to the public in November 2022. Two years later, two hundred million users use the OpenAI platform weekly. It was already possible to write code using ChatGPT, but Canvas opened new doors for programmers. The innovation is that developers and artificial intelligence work together to write code.
The program can be freely edited, reworked, or pasted from existing code.
This was not possible before. By December 10, 2024, OpenAI announced that Canvas had moved out of beta and was made available to all ChatGPT users, including those on the free tier.
Although the new extension is compatible with most programming languages, it is most effective for writing code in JavaScript, Java, PHP, C++, Python, and TypeScript.