how does this first function works?

Question

function addZero(x) {
if (x < 10) {
return "0" + String(x);
} else {
return String(x);
}
}

function printTime() {
var d = new Date();
var hours = addZero(d.getHours());
var mins = addZero(d.getMinutes());
var secs = addZero(d.getSeconds());
document.body.innerHTML = hours + ":" + mins + ":" + secs;
}
setInterval(printTime, 1000);

Why do I need to put String()? If I remove it works the same way.

Answer 1

String() function is converting int value into string, which is required in some languages, in some language like python, you cannot directly join a string and an int value, you have to convert that int into string by str() function.

But in JavaScript, it is not required. You can directly concate a string and an int here.

So feel free to remove that.