The primary UI authoring technology in Ember.js is Handlebars. Handlebars templates allow HTML fragments to embed dynamic content using Handlebars expressions placed inside double curly braces ({{ }}), the dynamic scripting blocks. Handlebars expressions perform data binding with attributes of routes, models, controllers, components, services, utils, and even application instances. Here is a sample Handlebars expression:
<h3>Welcome <strong>{{loggedInUser.fullName}}.</strong></h3>This code snippet expects an object (preferably derived from Ember.Object, though it binds with normal JS objects too) with the name loggedInUser, present somewhere in the context in the parent context hierarchy (template, controller, route, or application). Then, it establishes a one-way data binding with the fullName attribute of the loggedInUser object; hence, it just displays the value of the bound attribute.