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.
Prefix-Free is a JavaScript library that automatically removes browser vendor prefixes from CSS properties, enabling developers to use standard CSS without worrying about cross-browser compatibility issues.
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.