Glossary
Open-source AI
AI released under terms that allow anyone to use, study, change, and share it, usually including more than the weights.
In software, open source means code released under a license that lets anyone use, study, modify, and redistribute it. Applying the idea to AI is contested, because a model depends on its weights, training code, and training data, not just code.
The Open Source Initiative, which maintains the long-standing definition for software, has published a definition for AI that expects the weights, the code, and detailed information about the training data to be available under open terms. Many models marketed as "open source" do not meet that standard.
In news coverage, "open-source" is often used loosely for any model with downloadable weights. Check the license and what was actually released.