Donald Trump did not follow typical campaign advertising rules.
The Republican presidential nominee preferred to get so-called "earned media"—free publicity by appearing on cable news shows and other interviews.
He did so well that one estimate was that he had nearly $2 billion in earned media in the Republican primary alone.
Still, Trump eventually came around to airing ads, though they were much darker and more negative than a typical campaign.
Here's a brief look at his campaign ads this year.