join( )
The join( ) method joins the elements of an array into a string, and returns the string.
The elements will be separated by a specified separator. The default separator is comma (,).
var arr = ["George","John","Thomas"];
console.log(arr.join());
// George,John,Thomas
var fruits = ["Banana", "Orange", "Apple", "Mango"];
var a = fruits.join(" and ");
console.log(a);
// Banana and Orange and Apple and Mango