What is JavaScript?

JavaScript 

Once upon a time, there was the internet. You know, a bunch of computers all connected by wires. 

One person on a computer can read documents from another person's computer using a language called HTML. Each computer web browser can properly display these documents.

Add CSS to the mix and you have got a beautifully-styled web page. It is important to note that neither HTML nor CSS is programming languages. Back in 1995, a few people at Netscape started to wonder. 

What if there was a way to write a computer program for the browser? 

This way, when HTML and CSS get sent from one computer to another you can also send over some programming. This code would run in someone's web browser and create an even better user experience.

Thus JavaScript was born! 

You're probably familiar with Twitter. They use a lot of JavaScript on their web page to do things. Such as opening up a tweet in a bigger window for instance Also any of the actions below a tweet will trigger some JavaScript to be run.

If I click the star to favorite a tweet JavaScript will tell the servers. This tweet is now a favorite. 

If I click on reply you can see the JavaScript behavior at work yet again it focuses on the expanded reply box. All of this behavior is made possible by JavaScript It's worth mentioning that Java is not JavaScript.

They are two separate programming languages.

JavaScript is not just for programming in the browser, but on servers, game programming, databases, and even robots. We're only limited by our imaginations.