Mean.io is a platform for developing full-stack JavaScript applications using the MEAN stack, which consists of MongoDB, Express.js, AngularJS, and Node.js. It offers developers a coherent framework to create robust, scalable, and maintainable applications leveraging these technologies. Mean.io facilitates rapid development by providing a set of tools and a pre-configured environment to streamline the setup process and standardize development practices. The website, http://mean.io, serves as a resource for accessing documentation, tutorials, and community support, helping developers effectively build and manage their MEAN stack applications.