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.
cdnjs is a free distributed JS library delivery service.
Google Tag Manager is a tag management system (TMS) that allows you to quickly and easily update measurement codes and related code fragments collectively known as tags on your website or mobile app.
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.
Plesk is a web hosting and server data centre automation software with a control panel developed for Linux and Windows-based retail hosting service providers.
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.
Umbraco is an open-source Microsoft ASP.NET based content management system.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.