What is Open-source (open-weight) model?
An AI model whose weights are published so anyone can download, run and modify it — often for free.
Closed models (like the ones inside ChatGPT or Gemini) can only be used through their company's apps and APIs. Open-weight models can be downloaded and run on your own computer or server, adapted, and built into products.
The upside is control, privacy and cost; the downside is that you need decent hardware and some technical setup, and safety filters are up to you. “Open-source” is often used loosely — check the licence before commercial use.
Why creators care
Many free image apps are built on open-weight image models, which is why so many tools offer similar styles.
Related terms
Further training an existing AI model on a smaller, specific dataset so it gets better at one style or task.
A small add-on file that teaches an image model one specific face, product or art style without retraining the whole model.
A way for apps and developers to use an AI model from their own code, usually paid per use (per token or per image).
