Apache is a free and open-source cross-platform web server software.
Promise based HTTP client for the browser and node.js
cdnjs is a free distributed JS library delivery service.
jQuery CDN is a way to include jQuery in your website without actually downloading and keeping it your website's folder.
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.
Ubuntu is a free and open-source operating system on Linux for the enterprise server, desktop, cloud, and IoT.