cdnjs is a free distributed JS library delivery service.
Google AdSense is a program run by Google through which website publishers serve advertisements that are targeted to the site content and audience.
LiteSpeed is a high-scalability web server.
Twitter is a 'microblogging' system that allows you to send and receive short posts called tweets.
W3.CSS is a CSS framework developed by the World Wide Web Consortium (W3C), the main international standards organisation for the World Wide Web.