This lesson will teach you the basics of setting properties in your React components.
class App extends React.Component { render(){ let txt = this.props.txt return <h1>{txt}</h1> } } App.propTypes = { txt: React.PropTypes.string, cat: React.PropTypes.number.isRequired } App.defaultProps ={ txt: 'this is the default txt' } ReactDOM.render( <App cat={5} />, document.getElementById('app') );