ReactJS is JavaScript library used for building reusable UI components. According to React official documentation, following is the definition − React is a library for building composable user interfaces. It encourages the creation of reusable UI components, which present data that changes over time. Lots of people use React as the V in MVC. React abstracts away the DOM from you, offering a simpler programming model and better performance. React can also render on the server using Node, and it can power native apps using React Native. React implements one-way reactive data flow, which reduces the boilerplate and is easier to reason about than traditional data binding.

Some Important Topics


1. ReactJS Components: Learning the Basics
2. The Conventional React Component
3. States & Props
4. Component Ownership (a.k.a Parenting)
5. Component Interaction
6. TAGGING
7. COMMIT YOUR WORK AND CHECKOUT THE FILES
8. CLASS COMPONENT-ES6
9. Stateless Components
10. WRAP UP

Useful Tutorial/Websites From where you can learn React js