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.

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

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.

Cloudflare is a web-infrastructure and website-security company, providing content-delivery-network services, DDoS mitigation, Internet security, and distributed domain-name-server services.

DDoS-Guard is a Russian Internet infrastructure company which provides DDoS protection, content delivery network services, and web hosting services.

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

Varnish is a reverse caching proxy.