JavaScript - function syntax between ES5 and ES6

ES5

function foo() {
...
}

foo();

ES6

const foo = () => {
...
}

foo();

ES5_Return

function foo() {
    return 'Hello Taiwan';
}

ES6_Return

const foo = () => 'Hello Taiwan';

ES5_Return_Parameters

function foo(a, b) {
    return a+b;
}

ES6_Return_Parameters

const foo = (a, b) => a+b;

https://medium.freecodecamp.org/es6-functions-9f61c72b1e86
https://pjchender.blogspot.com/2017/01/es6-arrow-function.html
https://medium.com/@thejasonfile/es5-functions-vs-es6-fat-arrow-functions-864033baa1a