react class component render why code example

Example 1: class app extends component syntax

class Welcome extends React.Component {
  render() {
    return <h1>Hello, {this.props.name}</h1>;
  }
}

Example 2: lifecycle method react

INITIALIZATION= setup props and state 
MOUNTING= constructor->componentWillMount->render->componentDidMount//Birth
UPDATE= shouldComponentUpdate->componentWillUpdate->render
  		->componentDidUpdate //Growth
UNMOUNTING= componentWillUnmount //Death