List of JavaScript methods which you can use natively + ESLint Plugin

The Rocket Tools library is a lightweight set of Javascript methods for quicker and easier development.

A library of methods that extend upon the JavaScript String Object

Prototype method that calculates the percentage an element has been scrolled.

JavaScript Method Cheat Sheet that lists most methods and whether they are for strings or arrays or both. There is also indication of whether the method returns a new string or array, plus which array methods call a function.