cdnjs is a free distributed JS library delivery service.
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.
LiteSpeed is a high-scalability web server.
PHP is a general-purpose scripting language used for web development.
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.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.