how to join array of letters into words javascript code example

Example 1: javascript join array

var array = ["Joe", "Kevin", "Peter"];
array.join(); // "Joe,Kevin,Peter"
array.join("-"); // "Joe-Kevin-Peter"
array.join(""); // "JoeKevinPeter"
array.join(". "); // "Joe. Kevin. Peter"

Example 2: can you do a join() in js without the commas

arr.join("")