Apache is a free and open-source cross-platform web server software.
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.
Tippy.js is the complete tooltip, popover, dropdown, and menu solution for the web, powered by Popper.
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.