cdnjs is a free distributed JS library delivery service.
Cowboy is a small, fast, modular HTTP server written in Erlang.
Google Analytics is a free web analytics service that tracks and reports website traffic.
Google Hosted Libraries is a stable, reliable, high-speed, globally available content distribution network for the most popular, open-source JavaScript libraries.
Heroku is a cloud platform as a service (PaaS) supporting several programming languages.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Modernizr is a JavaScript library that detects the features available in a user's browser.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.