What are other ways humans can leave traces of information with the use of technologies?

Humans can leave traces of information through our technologies in really simple ways. This can be a website taking ‘cookies’ when we visit and recording how we might use the site. If we sign up for a newsletter or discounts from a site, that is information on our online habits. It can also include purchasing things online, or using the same email to sign up for different accounts. Information we give to apps like fitness trackers or period trackers have been known to sell out this information to big companies. These are all ways that our information can be traced online with out us overtly meaning it to.