app.js

import React from 'react';

const App = React.createClass({
    displayName: 'App',

    propTypes: {
        headline: React.PropTypes.string.isRequired
    },

    render: function render() {
        return (
            <h1 className="headline">
                {this.props.headline}
            </h1>
        );
    }
});

export default App;