It all began with DALL-E, a machine learning model developed by OpenAI to generate digital images from natural language descriptions. But it is closed source and not open to the public. Yet on August 22, 2022, the AI art community was shaken by the release of an open-source alternative, Stable Diffusion, which you can install and run locally using modest hardware. Within days, PCWorld described it as the new killer app. And it surely is.