What are other ways humans can leave traces of information with the use of technologies?
There are many ways that humans do this, personally I leave traces by using my debit card for online purchases, and filling out the shipping information.
Also when donating to companies they ask for your personal information and for your credit card details.
I have also noticed that when talking about something with a friend, ads for that exact thing can start popping up on my phone very shortly after. So I guess I am also leaving traces of information through conversations being picked up through my phone.