JavaScript is a high-level, dynamic, untyped, and interpreted programming language. It has been standardized in the
ECMAScript language specification. Alongside HTML and CSS, it is one of the three essential technologies of
World Wide Web content production; the majority of websites employ it and it is supported by all modern Web browsers without plug-ins. JavaScript is prototype-based with first-class functions, making it a multi-paradigm language, supporting
object - oriented , imperative, and functional programming styles.