Apache is a free and open-source cross-platform web server software.
cdnjs is a free distributed JS library delivery service.
DoubleClick Ad Exchange is a real-time marketplace to buy and sell display advertising space.
Google AdSense is a program run by Google through which website publishers serve advertisements that are targeted to the site content and audience.
Open Graph is a protocol that is used to integrate any web page into the social graph.
PHP is a general-purpose scripting language used for web development.