* **Declarative:** React makes it painless to create interactive UIs. Design simple views for each state in your application, and React will efficiently update and render just the right components when your data changes. Declarative views make your code more predictable, simpler to understand, and easier to debug.
* **Component-Based:** Build encapsulated components that manage their own state, then compose them to make complex UIs. Since component logic is written in JavaScript instead of templates, you can easily pass rich data through your app and keep state out of the DOM.
* **Learn Once, Write Anywhere:** We don't make assumptions about the rest of your technology stack, so you can develop new features in React without rewriting existing code. React can also render on the server using Node and power mobile apps using [React Native](https://facebook.github.io/react-native/).
You'll notice that we used an HTML-like syntax; [we call it JSX](https://reactjs.org/docs/introducing-jsx.html). JSX is not required to use React, but it makes code more readable, and writing it feels like writing HTML. We recommend using [Babel](https://babeljs.io/) with a [React preset](https://babeljs.io/docs/plugins/preset-react/) to convert JSX into native JavaScript for browsers to digest.
Whether you want to get a taste of React, add some interactivity to a simple HTML page, or start a complex React-powered app, the links in this section will help you get started:
The main purpose of this repository is to continue to evolve React core, making it faster and easier to use. Development of React happens in the open on GitHub, and we are grateful to the community for contributing bugfixes and improvements. Read below to learn how you can take part in improving React.
Facebook has adopted a Code of Conduct that we expect project participants to adhere to. Please read [the full text](https://code.facebook.com/codeofconduct) so that you can understand what actions will and will not be tolerated.
Read our [contributing guide](https://reactjs.org/contributing/how-to-contribute.html) to learn about our development process, how to propose bugfixes and improvements, and how to build and test your changes to React.
To help you get your feet wet and get you familiar with our contribution process, we have a list of [good first issues](https://github.com/facebook/react/labels/good%20first%20issue) that contain bugs which have a relatively limited scope. This is a great place to get started.