Apache is a free and open-source cross-platform web server software.
cdnjs is a free distributed JS library delivery service.
GetResponse is an email marketing app that allows you to create a mailing list and capture data onto it.
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.
Skimlinks is a content monetization platform for online publishers.