React is the library for web and native user interfaces. Build user interfaces out of individual pieces called components written in JavaScript. React is designed to let you seamlessly …

Quick Start Welcome to the React documentation! This page will give you an introduction to 80% of the React concepts that you will use on a daily basis.

至此，你已经了解了如何编写 React 代码的基本知识。 接下来你可以查看 实战教程 并把它们付诸实践，用 React 建立第一个迷你应用程序。

You can use as little or as much React as you need. Whether you want to get a taste of React, add some interactivity to an HTML page, or start a complex React-powered app, this section …

If you want to build your own solutions, see our guide to build a React app from Scratch for instructions on how to set up a new React project starting with a build tool like Vite, Parcel, or …

In 2023, we launched our new docs for React 18 as react.dev. The legacy React 18 docs are available at legacy.reactjs.org. Versions 17 and below are hosted on legacy sites.

If your app has constraints not well-served by existing frameworks, you prefer to build your own framework, or you just want to learn the basics of a React app, you can build a React app from …

Read Your UI as a Tree to learn how to create a render and module dependency trees for a React app and how they’re useful mental models for improving user experience and performance.

Instead of using an empty HTML file and letting React “take over” managing the page with JavaScript, they also generate the HTML automatically from your React components.

Components and Hooks must be pure – Purity makes your code easier to understand, debug, and allows React to automatically optimize your components and hooks correctly.