react-dom

React DOM is the package that provides DOM-specific methods for React, serving as the entry point to the DOM and server renderers. While the react package contains the core library for defining components and managing state, react-dom handles the actual rendering of those components to the browser DOM or to HTML strings for server-side rendering. The package exports the createRoot function for mounting React applications to a DOM container element, hydrateRoot for hydrating server-rendered HTML, and various utilities for portals and event handling. React DOM also includes the server rendering APIs through react-dom/server, providing renderToString, renderToStaticMarkup, and the streaming renderToPipeableStream and renderToReadableStream methods for Node.js and web streams respectively. This separation between react and react-dom was introduced in React 0.14 to enable React Native and other renderers to share the core react package. React DOM handles browser-specific concerns like event delegation, attribute mapping, and DOM element creation while React handles component logic and reconciliation.