Apache is a free and open-source cross-platform web server software.
cdnjs is a free distributed JS library delivery service.
Drupal is a free and open-source web content management framework.
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.
Progressive Web Apps (PWAs) are web apps built and enhanced with modern APIs to deliver enhanced capabilities, reliability, and installability while reaching anyone, anywhere, on any device, all with a single codebase.