Fastly is a cloud computing services provider. Fastly's cloud platform provides a content delivery network, Internet security services, load balancing, and video & streaming services.
GitHub Pages is a static site hosting service.
jQuery is a JavaScript library which is a free, open-source software designed to simplify HTML DOM tree traversal and manipulation, as well as event handling, CSS animation, and Ajax.
Microsoft Ajax Content Delivery Network hosts popular third party JavaScript libraries such as jQuery and enables you to easily add them to your web applications.
Open Graph is a protocol that is used to integrate any web page into the social graph.
Varnish is a reverse caching proxy.