It leads off right under the header with: "Mistral AI team is proud to release Mistral 7B, the most powerful language model for its size to date. Mistral 7B i

It leads off right under the header with: "Mistral AI team is proud to release Mistral 7B, the most powerful language model for its size to date. Mistral 7B is a 7.3B parameter model that...." So, it's a powerful language model that has 7.3B (billion) parameters. If you've been away long enough to not know what that means, this release article isn't going to be for you anyway, and so you may want to start with reading up on what a Large Language Model is and can do, how they have developed in the last few years, and then go from there.