The Browser Object Model (BOM) in JavaScript includes the properties and methods for JavaScript to interact with the web browser.
BOM provides you with a window objects, for example, to show the width and height of the window. It also includes the window.screen object to show the width and height of the screen.
Example
You can try to run the following code to learn how to get screen height and width −
<!DOCTYPE html>
<html>
<body>
<script>
document.write("Screen width: " + screen.width);
document.write("<br>Screen width: " + screen.width);
</script>
</body>
</html>