A component is that feature of React which comprises of an html along with it's associated JS satisfying the SRP principle.React components implement a render() method that takes input data as Component and returns the string after rendering as what to display. e.g.
<div id="mountNode"></div>
var CustomMessage = React.createClass({
render: function() {
return <div>Hello {this.props.name}</div>;
}
});
ReactDOM.render(<CustomMessage name="DNF" />, mountNode);
Output
---------- Hello DNF