Varnish is a reverse caching proxy.

Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.

LiteSpeed is a high-scalability web server.

PHP is a general-purpose scripting language used for web development.

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.

jQuery UI is a collection of GUI widgets, animated visual effects, and themes implemented with jQuery, Cascading Style Sheets, and HTML.

Popper is a positioning engine, its purpose is to calculate the position of an element to make it possible to position it near a given reference element.

FancyBox is a tool for displaying images, html content and multi-media in a Mac-style 'lightbox' that floats overtop of web page.

jQuery CDN is a way to include jQuery in your website without actually downloading and keeping it your website's folder.

Bootstrap is a free and open-source CSS framework directed at responsive, mobile-first front-end web development. It contains CSS and JavaScript-based design templates for typography, forms, buttons, navigation, and other interface components.