Online ads are pretty annoying, but without them, we would be out of a job. And the Internet wouldn't be able to exist. Online ads are part of an impressively complex network of technology.

CM Summit posted an interactive feature explaining how online ads work—in real-time—in a few simple steps. The process involves bouncing your data around the world in mere milliseconds. It is very impressive.

When you visit any website, your browser arrives with a detailed data profile that reveal your age, gender and also your location and a list of sites you've recently visited. This gives the website a way to know which ads to show you.

onlineads1.png

Using information like internet cookies, social media and more, an ad server can generate a unique profile of various metrics. With that code generated, the ad server will try to match it against a pre-sold inventory of ads. If the profile matches up, a relevant ad is served up in a split second.

When it doesn't fit, your request is then sent to an ad exchange that might be operated by anybody. They may have data on you which it will use to help serve you more relevant ads.

onlineads2.png

The request will first go on the auction block where different third parties will try to match their ads with your profile for the right price. In a few milliseconds, the impression is sold to the highest bidder and the ad is delivered to your browser.

onlineads3.png

It's amazing, not only on a technological aspect where so much sophistication is involved, but the fact that online advertisers know so much about you.

onlineads4.png

onlineads5.png

onlineads6.png

[Co.Design Check out the full interactive here.]