shift (JavaScript Array Method)

const tnwNums = [20, 30, 40, 50, 60, 70, 90];

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

function tnwFun2(){
    let result = tnwNums.shift();
    document.getElementById("demo").innerHTML = tnwNums.join(", ");
    document.getElementById("demo1").innerHTML = "The removed element is: " + result;
}