String split in JavaScript

const str = 'The quick brown fox jumps over the lazy dog.';

const words = str.split(' ');
console.log(words[3]);
// expected output: "fox"

const chars = str.split('');
console.log(chars[8]);
// expected output: "k"

const strCopy = str.split();
console.log(strCopy);
// expected output: Array ["The quick brown fox jumps over the lazy dog."]

Ref. https://developer.mozilla.org/ko/docs/Web/JavaScript/Reference/Global_Objects/String/split

String.prototype.split() - JavaScript | MDN