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.
Google Analytics is a free web analytics service that tracks and reports website traffic.
LiteSpeed is a high-scalability web server.
PHP is a general-purpose scripting language used for web development.
reCAPTCHA is a free service from Google that helps protect websites from spam and abuse.