NOTE 1: JavaScript introduction

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 what is JAVA Script.?

  •     It is the most powerful and widely use language right now. we can create websites, mobile apps, and games with javascript.


where does Java script code run.?

  • Java script was originally designed to run only in the browser, each browser has its own Javascript engine that runs the JS.

  • In 2009 a very claver engineer known as Rayan dawn took the open-source JS engine from chrome known as V8 and embedded inside c++ program. and that program is known as a NODE.

  • so, Node is a C++ program that includes google's v8  JS engine. so, now with help with it, we can run JavaScript code outside of the browser.
  • so we can pass our JavaScript code with Node for the execution, so it means we can treat JS like treating in backend service as well as mobile application services.
  • So, a nutshell Javascript code runs inside to the browser or node. browser and node provides runtime environment for our Javascript code.
what is the difference between Javascript and ECMAScript.?


  • ECMA script is just a specification where javascript is a programming language that confirms that specifications.
  • so we have an organization ECMA, which is responsible for defining standards. that takes care of that ECMA script specification.


  • Let's see Javascript in action.
  • every browser has javascript inbuilt. we can run javascript without any other tools.



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