Backbone

Backbone is a lightweight JavaScript library (sometimes described as a micro-framework) created by Jeremy Ashkenas that adds structure to JavaScript-heavy applications by providing models, views, collections, events and routing tied to RESTful JSON services. Its main philosophy is to provide the minimal set of primitives to organise your client-side code — models for data, collections for groups of models, views for UI interactions, and routers for state/URL management — without prescribing a full rigid framework. Because of this minimalism, Backbone integrates easily into existing applications and is flexible rather than opinionated, making it popular in the era before heavier single-page frameworks dominated. It helps developers avoid "spaghetti code" by separating concerns and centralising data-bindings and event flows. Even though newer frameworks have largely overtaken it in popularity, Backbone remains a valuable historical and educational reference.