The library has as a load of reusable cross-browser functions that perform common operations but with better performance gains

UnderscoreJs is pretty lightweight but packs some very useful methods for collection manipulations and templating in javascript. I used _.template() primarily for HTML templating and manipulating objects and collections. Methods like _.pluck and _.shuffle give powerful abstractions to filter arrays of objects without the need for heavy boilerplate code. The _.throttle and _.debounce methods come in handy when you need to throttle and control a burst of potentially repeated user inputs on a webpage. UnderscoreJs is also available on NodeJs platform as a managed dependency via npm registry.

Developer friendly utility library which does the task of functional operations for any web application.