Right now, the data you find on the Internet is more or less eternal. Sites come and go, sure, but traces remain, and as long as there's someplace to store information that information will persist. Maybe it shouldn't, according to a Dutch researcher, as if data degraded over time we'd enjoy more security and less piracy.
So, what does degrade mean in regards to data? Well, it could straight up be unreadable after a set amount of time, but more interesting is Dr. Harold van Heerde's proposal to have it become a "more general value." For instance, if a website sold your personal information to another company or spammer, your address would eventually store only what street you live on and, later, only what country you call home. This would, in turn, make it useless.
Still, it's a scary thought. How would we decide what data to make temporary? Would we even be able to discriminate? "In most cases there's no good reason for them storing data for so long," the good doctor said. He's probably thinking more in terms of the information a company stores when you make a credit card purchase online, however, and not so much the kind of stuff you'd toss onto the likes of Facebook.