Have you ever wondered why once you look at a product online you seem to see ads for it on every site you visit?  Often the ads are even further targeted to your specific tastes and interests.  How do they know what you’re looking at and what things you’re interested in?

There are multiple ways the companies that serve ads on the internet are tracking your browsing habits.  They use cookies, device fingerprinting, and cross-device tracking to build a profile on you.  Not all uses of these technologies are necessarily bad.  Cookies allow sites to remember your username, what you left in your cart, and other preferences you might have.

What is a cookie?

A cookie is a piece of digital information saved to the browser you use to access the Internet and its websites.  This information can be used to customize your browsing experience or to deliver targeted ads to you.

Who uses cookies?

First-party cookies are placed in your browser by the websites you visit.  They make the sites you frequently visit more efficient and personalized to you.  Examples you’ll recognize are:

  • Items in your shopping cart are retained when you leave the site
  • The site remembers your login name for you
  • Site preferences you may have set are remembered

Third-party cookies are placed in your browser by someone other than the website you are visiting.  Often the company hosting a website will partner with advertising networks who will place a cookie on your browser indicating what product you looked at if you click on an ad.  Now your browser will tell the ad network what products you’ve recently looked at no matter what website your visit.  So you’ll see ads for that product no matter where you go.  Other cookies can be placed on your browser to track your tastes and interests so ads can be better targeted to you.

In the next blog, we’ll discuss online tracking and how to control it.  Stay tuned.

Learn more about how you can block ads and trackers Click Here