Here’s an example of being tracked around the Internet that happened to me.
Yesterday I heard a product name on a podcast. I thought I recognised it so I looked it up (it was a sports bag my wife has).
In searching for it I visited the product page of an Australian seller (“The WOD Life”). At that point I remembered I actually bought the bag for my wife from that site a few years ago.
About 2 hours later I checked my emails and waiting for me was a new promotional email from the seller.
I haven’t received correspondence from them since I bought the bag.
My guess is, thanks to tracking cookies (advertisers, Google, etc.) I was tracked onto the site, which was then identified by an marketing company running campaigns for the seller, and they decided it was a good time to email me with a reminder to by more product.
A few years ago I came home from work to find my place had been broken into and I’d been robbed.
I felt violated by that experience.
Being tracked and targeted online like this holds the same feeling.