Apache is a free and open-source cross-platform web server software.
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.
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.
Modernizr is a JavaScript library that detects the features available in a user's browser.
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.
Ubuntu is a free and open-source operating system on Linux for the enterprise server, desktop, cloud, and IoT.
Unpkg is a content delivery network for everything on npm.