state and props

What is the Props
Props is short for properties and they are used to pass data between React components. React’s data flow between components is uni-directional
wt is State
which allows components to create and manage their own data

function tick() {
  const element = (
    <div>
      <h1>Hello, world!</h1>
      <h2>It is {new Date().toLocaleTimeString()}.</h2>
    </div>
  );
  ReactDOM.render(    element,    document.getElementById('root')  );}

setInterval(tick, 1000);