An introduction to Javascript

How Javascript was born ?

In 1993 the first web browser with a GUI was released. It was called Mosaic. Due to it’s GUI it made www quite popular.

It’s lead developers then founded Netscape which released an enhanced version called Netscape Navigator. The pages were static though. They lacked interaction.

To make the pages more interactive Netscape needed a scripting language. To do this they hired Brendan Eich. Same guy who later co-founded Mozilla project. His job was to put this language “in the browser”. The first version was completed in 10 days. It was called Mocha. Then renamed to Livescript and subsequently to Javascript.

What exactly is Javascript ?

Javascript is an interpreted or just in time compiled programming language. What this means is that the program you write is compiled at run time.
Unlike Java where you need to first compile the program and then run the generated byte code.

It is one of the core technologies of the World Wide Web (www) along with HTML and CSS. You can build interactive websites using JS. When you see some animations like page elements fading in and out or resizing then it’s more or less the work of JS.

All major web browsers have a dedicated JS engine which can execute the JS code.

Most of the websites you see use Javascript to handle client side behavior. But with the advent of technologies like Node JS we can now write code in JS which can be executed on Server side.

Why should you learn Javascript ?

To build any modern day website Javascript is required. And now JS can be used to build backend, like APIs. So whether you want to work for a company as a developer or you plan to build your pwn websites you will need JS.

Code – https://github.com/ankur-srivastava/javascript-lectures/tree/master/Lecture1

PPT – Introduction to JavaScript from Ankur Srivastava