It's 2020 and you're 13 years old. There is very little delineation between real life and the Internet. Your face computer ensures that an IM, text, photo or video is only a blink away. Your friends are nearly always accessible and you can hang out virtually just as easily as you can IRL.

You have no need to engage in a public forum, except on your terms. Social networking is baked into your everyday experience the way the web was synonymous with computers and mobile devices back in 2013.

Where does Facebook fit in in this scenario? It's still hugely popular and influential — with your parents. In other words, Facebook has become Yahoo.

Snicker if you must. Yahoo these days is that '90s throwback Marissa Mayer is desperately trying to resurrect. At one time, though, Yahoo was as dominant on the web as Facebook is today. Fifteen years ago, Yahoo was the No. 1 destination on the web with 40 million monthly visitors. That may sound like pocket change compared to Facebook's 1.1 billion, but consider that there were only 140 million people on the web at the time.

True, Yahoo at its peak wasn't as dominant as Facebook is today. Back in 1998, about one-third of web users visited Yahoo. Today, with a global audience of 2.4 billion, Facebook has about half. That said, from a raw numbers standpoint, Yahoo is still no slouch. About 700 million people each month visit Yahoo's sites, and in the U.S. at least, Yahoo gets more visitors than Facebook.

So why is Facebook still considered a much hotter company than Yahoo? Demographics. Facebook overindexes on users under 18 and especially on 18- to 24-year-olds, according to Quantcast. Yahoo underindexes on those below 18 and only slightly overindexes on 18- to 24-year-olds.

Can Facebook maintain that dominance in the youth market? It's certainly possible. As Rob Callender, director of youth insights for The Futures Company, a Chicago-based researcher notes, Apple and Nike have managed to be cool with teens year after year.

That said, Callender's latest research shows that teen use of Facebook has plateaued. Despite reports to the contrary, though, they aren't abandoning the platform in droves. "It's been a decline that isn't significant," he says. Part of the issue is the oft-cited phenomenon of kids being spooked by elder family members suddenly friending them. "Once people found out that aunts and grandfathers followed them, their enthusiasm went up in a puff of smoke," Callender says. (Seeing a 50-year-old with an iPhone apparently doesn't have the same effect.)

Ruby Karp, a 13-year old, explained the problem in a recent piece about Facebook on Mashable: "All of our parents and parents' friends have Facebooks. It’s not just the fact that I occasionally get wall posts like, 'Hello sweetie pie!' But my friends post photos that get me in trouble with those parents."

Luckily for Facebook, there's no social media behemoth there to take its place. Instead, teens are being siphoned away by Snapchat and messaging apps. Given teens' penchant for privacy, these closed-loop networks represent a potent threat to Facebook, which is taking steps to become a more public platform.

The wild card in this mix is Google Glass. If such wearable computing becomes popular and within a few years filters down to teens, it could drastically change the way they consume media. Facebook has shown it can adapt to mobile, but bringing that experience to something like Google Glass will be a challenge on top of a challenge. Just as with mobile, Facebook's aesthetic advantage will be lost; on Glass it will be just another app. Here, Facebook's key selling point — its huge user base — will work against it as teens seek more intimate experiences.

In such a doomsday scenario, Facebook won't disappear. Like Yahoo, it will stick around along with its huge, aging user base. Still making money, but with its glory days behind it, Facebook will once again prove the maxim that demographics is destiny.

Image: Mashable