This is the first stable release of @remix-run/router, which provides all the underlying routing and data loading/mutation logic for react-router. You should not be using this package directly unless you are authoring a routing library similar to react-router.
For an overview of the features provided by react-router, we recommend you go check out the docs, especially the feature overview and the tutorial.
For an overview of the features provided by @remix-run/router, please check out the README.