Alongside HTML and CSS, JS is one of the core technologies of the World Wide Web. JS enables interactive web pages and is an essential part of web applications. The vast majority of websites use it, and major web browsers have a dedicated JS engine to execute it.
As a multi-paradigm language, JS supports event-driven, functional, and imperative (including object-oriented and prototype-based) programming styles. It has APIs for working with text, arrays, dates, regular expressions, and the DOM, but the language itself does not include any I/O, such as networking, storage, or graphics facilities. It relies upon the host environment in which it is embedded to provide these features.
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