I heard a man on the radio talking about how to make money from your website. Among things like Google Adsense, he discussed becoming an Amazon Affiliate. According to him, if someone went to your site that had the Amazon Affiliate item on the page, Amazon would set a cookie that would last for a certain amount of time, and if that user then went to Amazon and bought ANYTHING, you would receive commission. I'm almost afraid to ask, but is that true? I have checked my cookies after visiting such sites, and Amazon does indeed set something up.

The only thing I could find about this was their affiliate program (https://affiliate-program.amazon.com/) which does something similar but the user has to click a link and buy it for you to earn credit.

So it's if they actually click the ad, and then buy something from Amazon. Not if they just visit your page with the ad and then go to Amazon and buy something?

That's what I got from the site. You might want to look around more though.

I'll look into it more, but I think that must be it. I did some more tests with visiting pages that sell Amazon items, and Amazon set more cookies in your browser if you clicked the link than if you just visited the pages that displayed them.