The function print(message)?

Dave the instructor put this function in this code, and all it does in this situation is do the whole document.write thing. He's doing this so that there isent any DRY code. he can just pass a new message threw the function any time he want to put something else in the print function. It would be the same as just using the document.write in this situation.

Just keep going at it. The instructor revealed a compelling reason for why he wrote it that way near the end of the course. It had something to do with the fact that the document.write function is frowned upon. He then went on to introduce a better method for writing to the document:

function print(message) {
  var outputDiv = document.getElementById('output');
  outputDiv.innerHTML = message;

Thus, by factoring out the print function, all we had to do to update the change was to change the print function like so, above. All points in our document where we called the print function would then reflect this change. So it does indeed concur to DRY programming principles. I had assumed that since document.write was a simple function then it wouldn't be necessary to factor it out. It turns out that the more important reason for doing so is that if there is some new method of accomplish something it would then make updating our functions a lot easier.

I'm still confused about the print(message) function.

function print(message) { document.write(message); }

The "message" is not declared anywhere as mentioned before.

All the print function does it that it prints whatever you pass to it as an argument. In this instance it writes to the html document using document.write. We could have just document.write(listHTML) instead of print(listHTML) and we would have the same result. Hence, I think he could have included it merely for semantic purposes to correspond accordingly with printList. For me at least, I find the argument that it was included to demonstrate DRY programming principles tenuous, as the function just included one line of code.

James - thank you for the link. What a great explenation!