Hi, I am learning javaScript and jQuery. In this code, I saw that if I keep the script in the head section it doesn't work.But if I keep the script in the body section it works. Can you please tell me why this happens? Thank you in advance.
<!DOCTYPE html>
<html>
<body>
<h3>Your Screen:</h3>
<div id="demo"></div>
<script>
var txt = "";
txt += "<p>Total width/height: " + screen.width + "*" + screen.height + "</p>";
txt += "<p>Available width/height: " + screen.availWidth + "*" + screen.availHeight + "</p>";
txt += "<p>Color depth: " + screen.colorDepth + "</p>";
txt += "<p>Color resolution: " + screen.pixelDepth + "</p>";
document.getElementById("demo").innerHTML = txt;
</script>
</body>
</html>