Upworthy’s secret to traffic generation involves this one simple insight

Upworthy succeeds in driving piles of traffic not because because it uses some sophisticated new technology.

Upworthy succeeds because it recognizes that its readers are human beings, not abstract “traffic” or “eyeballs.” This is an old technique applied to the web.

As Derek Thompson explains in his report on Upworthy’s success, its writers select stories that have emotional appeal and craft headlines to pique our curiosity. They combine this with optimization techniques to find out what works best:

Upworthy has mastered the dark viral arts with a unique blend of A/​B technology and lily-white earnestness. The staff scours the Web for “stuff that matters,” writes multiple headlines for a test audience, selects the top-performer, and blasts it out on social media. It’s a deceptively simple plan that’s devouring the Internet, one Facebook Newsfeed at a time. The site nearly surpassed 50 million unique visitors in October, which suggests traffic comparable to giants like Time​.com, and Fox News. …

What’s the “secret”? An entertaining slideshow of Upworthy’s headline-writing strategies last year repeatedly references the “curiosity gap.” The idea is both to share just enough that readers know what they’re clicking and to withhold just enough to compel the click.

That linked slideshow is definitely worth reading through.