Sugar augments the existing JavaScript environment with helper methods on existing objects. From fixing broken support of standard methods, widening acceptable arguments, multi-lingual and improved regex support on strings, nice supplementary string methods like words(), and shortcut methods to Math object methods. Additional helpers for Dates, Objects, Functions and Regex. An library for a consistentising JavaScript across different imlementations.
Addy Osmani introduces backbone.js as one part of the toolkit for building mobile JavaScript web applications. Backbone is an MVC-like framework to structure your application, simplifies server-side persistence, decouples the DOM from data, succinctly separates apps into Models, views and routers and provides synchronisation between DOM, model and collections.