Alexa Certified Site Metrics is an analytics service wich monitors and analyses web traffic and can be used to keep track of user behavior.
Apache is a free and open-source cross-platform web server software.
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.
ShareThis provides free engagement and growth tools (e.g., share buttons, follow buttons, and reaction buttons) for site owners.