Ember.js: Ember.js is an opinionated framework that helps developers build ambitious web applications. It’s known for its conventions, which make it easy to maintain and scale large applications. Ember.js has an active community, rich documentation, and provides tools for building rich user interfaces.
Backbone.js: Backbone.js is a lightweight framework that provides a simple structure for building complex web applications. It’s known for its flexibility, and it allows developers to use any combination of libraries they want. Backbone.js provides models, collections, and views to create scalable and maintainable web applications.