"I'm sorry. Our intentions were good."

Ethan Zuckerman was a designer and programmer for the early web-hosting service Tripod.com when a car company freaked out. The unspecified manufacturer had bought a banner ad on a page that "celebrated anal sex," and was not too pleased at the association of its brand with sexual escapades. Tripod had the solution: what if an advert could launch in its own window? Zuckerman wrote the code for the world's first pop-up ad, and for many years it was impossible to browse without being inundated by pop-ups.

You'll still find some pop-ups in the seedier parts of the internet, of course, but they're few and far between. Thanks to work from Netscape and Opera, who were the first to add pop-up blockers into their products, the majority of web browsers now prevent sites from launching hundreds of ad windows. Regardless of public opinion, the pop-up ad was instrumental in defining advertising as the primary business model for websites, but Zuckerman now believes there's a better way. In a long essay for The Atlantic, he explains how online advertising became the behemoth that it is, and what we can do about it.