keys (JavaScript Array Method)

const tnwNames = ["Hla Hla", "Mya Mya", "Soe Soe", "Moe Moe"];
let result = "";

function tnwFun1(){
    document.getElementById("demo").innerHTML = tnwNames.join("
");
}

function tnwFun2(){
    let tnwKeys = tnwNames.keys();
    for(let x of tnwKeys){
        result += x + "
";
        document.getElementById("demo").innerHTML = result;
    }
}