what does split do in js code example

Example 1: string split javascript

var myString = "An,array,in,a,string,separated,by,a,comma";
var myArray = myString.split(",");
/* 
*
*  myArray :
*  ['An', 'array', 'in', 'a', 'string', 'separated', 'by', 'a', 'comma']
*
*/

Example 2: javascript split

// bad example https://stackoverflow.com/questions/6484670/how-do-i-split-a-string-into-an-array-of-characters/38901550#38901550

var arr = foo.split(''); 
console.log(arr); // ["s", "o", "m", "e", "s", "t", "r", "i", "n", "g"]

Example 3: javascript split

var arr = ['hey', 'nay', 'wey'];
var let = arr.split(' ');
console.log(let);