What is JavaScript?
JavaScript is the programming language of HTML and the Web.
JavaScript is a dynamic, popular client-side scripting language that is lightweight and commonly used with HTML. Using JavaScript programmers can do a client-side script to interact with the user for making dynamic pages.
Need of JavaScript?
The purpose of JavaScript language, when used in web development, is to manipulate the web page elements and to make it dynamic. Imagine a web page that contains just text content. You can read it and you can even click on links to move to the next page, but your interaction with the page would be limited. What if you would like to click on a link or a button and hide a part of the page? Perhaps you would like to make an image move from one side of the page to another. JS would allow you to do this.
New technology of Javascript :
Angular JS
AngularJS is a JavaScript framework. It can be added to an HTML page with a tag. AngularJS is perfect for Single Page Applications.
AngularJS is open source, completely free, and used by thousands of developers around the world. It extends HTML DOM with additional attributes and makes it more responsive to user actions AngularJS is distributed as a JavaScript file, and can be added to a web page with a script tag.
React
React is mostly the V in MVC. It focuses entirely on that piece of MVC and disregards the architecture of the rest of your application.
It provides a component layer that makes it easier to make UI elements and combine them together
Backbone
Backbone provides a full MVC framework along with routing. The Models allow for key-value binding and events for handling data changes. Models (and Collections) can connect to RESTful APIs.
jQuery
jQuery is the most used JavaScript library in the world, and no app should ever go without it unless you dislike programmer productivity. It makes DOM traversal, event handling, animation, AJAX so much simpler and easier across all browsers.
D3.js
Data visualization and charting is a common requirement for web applications In D3 you to manipulate data documents from any source and apply a transformation into the DOM.
Babylon.js
In Babylon.js You can create incredibly high-quality games complete with physics, audio, and particle systems among other things.
Three.js
It is a lightweight 3D library. that allows rendering 3D to an HTML5 canvas.
Phantom JS
Phantom JS allows you to run a headless Webkit. the rendering engine behind Safari and previously Chrome.
