facebook/create-react-app

Create React App is a command-line tool that scaffolds a new React web application with no manual build configuration. The README is explicit that the project is now deprecated and recommends migrating to one of the React frameworks documented on the React.dev "Start a New React Project" page; it remains useful for tutorials but is not recommended for new production apps. The problem it tackled: setting up a modern React project used to mean wiring together a bundler, a transpiler, a linter, a dev server, and a test runner before you could write a component. Create React App reduced that to one command, npx create-react-app my-app, which produces a folder with all source files, a dev command (npm start) that opens the app on localhost:3000 with live reload, a test command (npm test), and a production build command (npm run build) that produces a minified, hashed bundle ready to deploy. How it works: the tool installs a single curated dependency that bundles webpack, Babel, ESLint, and other tools so the user does not see or configure them directly. The README calls this "one dependency, no configuration required, no lock-in" and describes an "eject" command that copies all the hidden configuration into your project if you ever want to take it over. The generated project supports React, JSX, ES6, TypeScript and Flow syntax, autoprefixed CSS, a test runner with coverage, a live dev server, sourcemaps in production, and an optional service worker plus web app manifest for Progressive Web App use. You would have used it as a beginner-friendly entry point for learning React or quick prototypes. For new work today, the README points readers to alternative React frameworks. The primary language is JavaScript and it requires Node 14.0.0 or later.