AddThis is a social bookmarking service that can be integrated into a website with the use of a web widget.
Azure is a cloud computing service for building, testing, deploying, and managing applications and services through Microsoft-managed data centers.
cdnjs is a free distributed JS library delivery 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.
reCAPTCHA is a free service from Google that helps protect websites from spam and abuse.
Typekit is an online service which offers a subscription library of fonts.
UIKit is the framework used for developing iOS applications.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.