jQueryjQuery is a fast, small and feature-rich JavaScript library. It makes things like HTML document traversal and manipulation, event handling, animation and Ajax much easier with an easy-to-use API that works in a variety of browsers. With a combination of versatility and extensibility, jQuery has changed the way millions of people write JavaScript. source is a fast, small and feature-rich JavaScript library. It makes things like HTML document traversal and manipulation, event handling, animation and Ajax much easier with an easy-to-use API... the abbreviation from English for: application programming interface An API is an interface to interact with a service. https://youtu.be/KLe2lCEy-Xw that works in a variety of browsers. With a combination of versatility and extensibility, jQueryjQuery is a fast, small and feature-rich JavaScript library. It makes things like HTML document traversal and manipulation, event handling, animation and Ajax much easier with an easy-to-use API that works in a variety of browsers. With a combination of versatility and extensibility, jQuery has changed the way millions of people write JavaScript. source has changed the way millions of people write JavaScript.