React is a java script library that is used to build user interfaces. You can make reusable components which can display data and data can be change over time without reloading the page. React was created at Facebook and Instagram on 2013
React Native enables you to create native mobile applications
React Developer Tools
You can find some useful developer tools for React development
Firefox developer tool allows you to inspect a React tree, including the component hierarchy, props, state, and more.
You can find another development tool which can be used in your Google Chrome
Speed Rendering with React
When you develop modern web application like single page application you have to pay your attention on DOM manipulation.
You can understand it with following example
This kind of inefficient update leads to serious issues when you deal with application with large DOM
React can overcome this issue with Virtual DOM
What is Virtual DOM?
When you develop React app every DOM Object has identical Virtual DOM Object. This Virtual DOM object is a light weight copy of the real DOM Object
Virtual DOM has the all properties what you find in DOM but it does not have some features needed to draw on screen.
You can manipulate the Virtual DOM faster than DOM because Virtual DOM has nothing to draw on screen