when should i use arrow functions in es6 code example

Example: es6 arrow function

//ES5
var phraseSplitterEs5 = function phraseSplitter(phrase) {
  return phrase.split(' ');
};

//ES6
const phraseSplitterEs6 = phrase => phrase.split(" ");

console.log(phraseSplitterEs6("ES6 Awesomeness"));  // ["ES6", "Awesomeness"]