add images from my computer to react app code example

Example 1: how to use saved image on react

<img alt="timer" src={require('./images/timer.png')} />

Example 2: React import image with url

import React from 'react';
import ReactDOM from 'react-dom';

const App: FunctionComponent = () => {
  return (
    <img src = {this.props.url} alt='something'/> 
  );
}