toString()

const myArray = [1, 2, 3, 4, 5];
const arrayAsString = myArray.toString();
console.log(arrayAsString);

join()

const myArray = [1, 2, 3, 4, 5];
const arrayAsString = myArray.join(', ');
console.log(arrayAsString);

HTML CODE

<input type="checkbox" id="myCheckbox" onchange="checkBoxChanged()">
<div id="status"></div>

JAVASCRIPT CODE

function checkBoxChanged() {
    var checkBox = document.getElementById("myCheckbox");
    var statusDiv = document.getElementById("status");
    
    if (checkBox.checked) {
        statusDiv.innerHTML = "Checkbox is checked.";
    } else {
        statusDiv.innerHTML = "Checkbox is not checked.";
    }
}