Apache is a free and open-source cross-platform web server software.
cdnjs is a free distributed JS library delivery service.
Etracker is a web optimisation solution.
Google AdSense is a program run by Google through which website publishers serve advertisements that are targeted to the site content and audience.
WP Rocket is a caching and performance optimisation plugin to improve the loading speed of WordPress websites.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.