Apache is a free and open-source cross-platform web server software.
cdnjs is a free distributed JS library delivery service.
Vimeo is a video hosting, sharing and services platform. Vimeo operation an ad-free basis by providing subscription plans.
W3.CSS is a CSS framework developed by the World Wide Web Consortium (W3C), the main international standards organisation for the World Wide Web.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.