How can I add a class to a DOM element in JavaScript?

Question

How do I add a class for the div?

var new_row = document.createElement('div'); 

Answer 1

This answer was written/accepted a long time ago. Since then better, more comprehensive answers with examples have been submitted. You can find them by scrolling down. Below is the original accepted answer preserved for posterity.

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new_row.className = "aClassName"; 

Here's more information on MDN: className