When building apps on Node.js, we use the same Backbone models and collections on both client and server. The difference is the Backbone.sync implementation: *

When building apps on Node.js, we use the same Backbone models and collections on both client and server. The difference is the Backbone.sync implementation: * On client Backbone.sync does AJAX calls * On server Backbone.sync talks to database In some cases we also do Backbone.sync via socket.io Note: Backbone.sync is the method all I/O operations on Backbone.js models and collections call. You can either use the default AJAX-based implementation that Backbone.js ships with, or override it with your own.