When you browse the web and visit e-commerce sites, they often place a small piece of code called a cookie or use tracking pixels (from Facebook, Google, etc.) in your browser. These track your browsing behavior, like the products you viewed, added to your cart, or purchased.

After you make a purchase or even just look at products, these tracking mechanisms follow you across the web, allowing businesses to serve ads for similar or complementary products based on your recent behavior. It's time to turn the tables, and use this incredible data to zero in on your unique audience. Here's how..