PANews reported on April 1st that according to IT Home, OpenAI CEO Sam Altman officially announced today that he will release a "powerful new open-weight language model" with reasoning capabilities in the coming months. So far, users can only use its models through OpenAI's interface or by integrating its API keys into their applications, which means the model itself remains secret and proprietary. However, open-weight models are different. The pre-trained parameters (the "weights" that define how the model responds) in these models are publicly shared. Developers and researchers can download them, run them locally, fine-tune them for specific use cases, or insert them into custom applications.

It is worth noting that just because the weights are open does not mean they are open source. Training code, datasets, and detailed logs may still remain proprietary or undisclosed, so they may not be completely open source.