This definition is correct. Ampersandjs is really a non-frameworky framework. Now question comes, Why Ampersand.js?. Because we love Backbone.js, and Ampersand.js is written on the top of Backbone.js. For more details, please refer http://ampersandjs.com.
In this article, I am explaining you to build a simple single page application (not simple as much as any hello world or todo app :)) using rails and ampersand.js. The application will be wired-up with a Rails application and will fetch all its data from rails generated APIs. In fact, behind the scene, Rails application is providing the APIs directly from the file