As it happens, lots of people found del.icio.us valuable right from the start, making it a proverbial grassroots hit. Schachter did no advertising, no marketing. But the site was so successful that in 2005 he quit his day job at Morgan Stanley, raised some money from outside investors, and launched del.icio.us as a regular business. Less than a year later, Schachter sold del.icio.us to Yahoo, where he now works in the Groups business, running the site full time.
Schachter’s original focus on the individual user has never wavered, and it remains essential to the way del.icio.us works. But as more and more people started to use the site, something interesting happened: when aggregated, all those individual tags created a useful system for categorizing Web pages. On the surface, del.icio.us doesn’t seem designed to do this, since each person makes his or her own tags, and there’s no overarching authority to maintain order. But even with no one in charge, the product of all the individual decisions of del.icio.us’s users is surprisingly well organized–and surprisingly intelligent. That is, if you do a search on del.icio.us for all the pages that are tagged with a particular word, you’re likely to come up with a remarkably good–and well-rounded–selection of related Web sources. In other words, although del.icio.us didn’t need lots of users to be useful, once it had lots of users, it became valuable in an entirely new way. Almost accidentally, it became an excellent tool for making sense of the Web.
What del.icio.us’s users were creating–without necessarily knowing they were doing so–was what technology blogger Thomas Vander Wal has dubbed a “folksonomy,” a flexible system of organization that emerges organically from the choices users make. We’re all familiar with the alternative, the kind of rule-bound, top-down classification scheme that Internet theorist Clay Shirky calls “ontological” in nature. The Dewey decimal system is an example: every object is assigned its place in a hierarchical system of organization, and every object is defined as, ultimately, one thing: a book goes in one place in the library and nowhere else. In a folksonomy, by contrast, definitions are fuzzier. With del.icio.us, the same Web page has many different tags, which often aren’t even related to one another, and no explicit rules are being followed. Web pages are therefore listed not in one place but in many places, and sometimes pages aren’t quite where you might expect them to be. So folksonomies are messier than “ontologies” are.
What del.icio.us has shown, though, is that folksonomies’ imperfections are outweighed by their benefits. In the first place, folksonomies are dynamic rather than static. A Web folksonomy thus allows us to reclassify content according to our changing interests. An academic paper that’s interesting today might be equally interesting a decade from now–but why it’s interesting, why people care about it, might be very different. A traditional categorization system has a hard time dealing with this: once the essence of an object is defined, it’s supposed to be defined for good. In a folksonomy, the reclassification happens almost automatically–as people start tagging the paper with new, more relevant tags, for example. Web folksonomies are also better at capturing the multiple meanings and uses that a given site has, rather than constraining the possible range of meanings. It’s useful, after all, to learn that many people have tagged stories about Mark Cuban “crazy,” in addition to indicating everything else that’s important about him. Finally, folksonomies are cheap. Imagine the labor and the time it would take to construct a traditional organizing system for all the pages on the Web, and then to maintain and update it. Then recognize that del.icio.us is producing a ceaselessly revised organizing system–at almost no cost.