What is the difference between jsdom.env() and jsdom.jsdom?

I am still foggy开发者_StackOverflow社区 about how to used jsdom. What is the difference between jsdom.env() and jsdom.jsdom?

The readme file explains that

jsdom.env is built for ease of use, which is rare in the world of the DOM! Since the web has some absolutely horrible javascript on it, as of jsdom 0.2.0 jsdom.env will not process external resources (scripts, images, etc). If you want to process the javascript use one of the methods below (jsdom.jsdom or jsdom.jQueryify)