Apache is a free and open-source cross-platform web server software.
cdnjs is a free distributed JS library delivery service.
Contao is an open source CMS that allows you to create websites and scalable web applications.
jQuery CDN is a way to include jQuery in your website without actually downloading and keeping it your website's folder.
jQuery UI is a collection of GUI widgets, animated visual effects, and themes implemented with jQuery, Cascading Style Sheets, and HTML.
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.
PHP is a general-purpose scripting language used for web development.