I don't use google search engine ever but ever since I bought silverware at jc penneys for my granddaughters wedding gift I have seen ads for silverware on what ever website I am on. Since I have already bought this item why in heavens name do they keep bombarding me with ads it pisses me off so how does this help a consumer or the company advertizing? This has happened to me on so many items I purchase online that is one of the cons for shopping online. My smart phone I decided will not be smart I don't connect it to the internet I have no need to be online when out in public since I am retired and have enough time at home to do all I want online.
It's usually because of a thing called AdChoices, a company that runs the banner ads on a large number of Web sites. When you visit a company Web site that's advertising with AdChoices, they put a cookie (a small piece of data) on your computer, and when you visit a site that has banner ads through AdChoices, they will read that cookie and if one of those advertisers is in that cookie, it will display more ads from that advertiser. Of course, a lot of the time, it ends up putting ads for something you already just bought, which is useless.
Now, most AdChoices ads can be filtered out by using a "private browsing" feature that's in all the major browsers when you're visiting an online store. It's not totally foolproof, though, and I've found that Facebook's ads (which also use AdChoices) have sometimes been far more insidious.