Amazon Web Services (AWS) is a comprehensive cloud services platform offering compute power, database storage, content delivery and other functionality.
cdnjs is a free distributed JS library delivery service.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Unpkg is a content delivery network for everything on npm.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.