What is the difference between React and ReactDOM?

The

react

package contains

React.createElement()

,

React.Component

,

React.Children

, and other helpers related to elements and component classes. You can think of these as the isomorphic or universal helpers that you need to build components. The

react-dom

package contains

ReactDOM.render()

, and in

react-dom/server

we have server-side rendering support with

ReactDOMServer.renderToString()

and

ReactDOMServer.renderToStaticMarkup()

.