Practice React while learning step by step
References:
https://stackoverflow.com/questions/31354559/using-node-js-require-vs-es6-import-export
https://reactjs.org/tutorial/tutorial.html
https://hacks.mozilla.org/2015/06/es6-in-depth-arrow-functions/
Destructuring assignment： https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Destructuring_assignment
HTML Event Attributes： https://www.w3schools.com/tags/ref_eventattributes.asp