Comment by vikingcaffiene

The author makes compelling arguments but I respectfully disagree with their conclusion. Null exists for cases where you want to set the the absence of a value intentionally. It is literally the value of having no value. Undefined exists for cases where no value has yet been set. It's a subtle but important difference and allows a certain amount of nuance and expressiveness in ones code to communicate intent. I do think it's fair to say that a lot of devs don't use them that way. They _are_ for separate use cases though.