JavaScript

JavaScript, commonly known as "JS", is a cross-platform, object oriented scripting language. Alongside HTML and CSS, JavaScript is considered one of the three core technologies of World Wide Web content production. JS can be used to check or modify contents of forms, open windows and even to write dynamic page content. So, one might even go ahead and say that JavaScript is included to web pages to make them more interactive. But that's not all -- JavaScript is also the foundation of a lot of commonly used libraries like jQuery and frameworks like AngularJS and NodeJS.

JavaScript is prototype based with first class functions. This makes it a multi-paradigm language that supports object-oriented, functional and imperative programming styles. JS contains an API for working with text, arrays, dates as well as regular expressions. So, basically, it comprises of a standard library of objects such as, Array, Date and Math, along with a core set of language elements such as operators, statements and control structures. However, it does not include any I/O, such as networking, storage, or graphics facilities for that matter.

There is a bit of a misconception that JavaScript and Java are the same, when in fact they are totally unrelated. To simply put it, JavaScript is a client side, interpreted, object oriented, high level scripting language, whereas Java is a client side, compiled, object oriented high level language.

Being a scripting language, JavaScript cannot run on its own, hence making the browser responsible for running JS code. Therefore, when a user requests HTML page containing JavaScript, it becomes the browser's responsibility to execute it. JavaScript supports all the modern browsers there are, relieving us of the burden that is being made to only use a specific browser which supports it.