Based on Simon Willison's original 2005 eTech talk, Simon expands this into a full article covering the expressive functionality of JavaScript. He covers the basics of JavaScript: literals, variables, functions, scope, control flow, objects, classes, inner functions and closures. Everything a developer needs to know before diving into more advanced JavaScript.
Eric Miraglia explains Douglas Crockford's Module pattern, a way of creating encapsulated JavaScript functions that offer private and public methods and properties. It uses an anonymous function that returns an object containing our methods, and avoids the big issue of cluttering up the global namespace with global functions. Its based on the Singleton pattern.