Apache is a free and open-source cross-platform web server software.
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.
Matter.js is a 2D physics engine for the web. It provides JavaScript-based tools for simulating rigid body physics in 2D environments.
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.