As I described here, I’ve been baffled by why Barnes & Noble keeps showing me ads that include a book I wrote.  I was finally smart enough to track this down and, as people suggested, it has to do with cookies.  Turns out there’s a little hard-to-see link in these  ads.  Click it, and it brings you to an explanatory page that includes an opt-out option.  The company behind the ads is called Criteo, and the technology is called personalized retargeting.  It’s been around for years.  Here’s a New York Times article about it from 2010:

People have grown accustomed to being tracked online and shown ads for categories of products they have shown interest in, be it tennis or bank loans.

Increasingly, however, the ads tailored to them are for specific products that they have perused online. While the technique, which the ad industry calls personalized retargeting or remarketing, is not new, it is becoming more pervasive as companies like Google and Microsoft have entered the field. And retargeting has reached a level of precision that is leaving consumers with the palpable feeling that they are being watched as they roam the virtual aisles of online stores.

So, my cookies tell the software that I’ve visited the pages for Richard Bowker novels on the Barnes & Noble web site.  And the software puts up ads that keep reminding me of these very fine novels until I break down and buy one.  This is one of those technologies that is equal parts helpful and creepy. I’m not quite ready to get off the grid, like Jack Reacher, but maybe the day will come.