When you think of social networking, what names come to mind? For many people, the obvious answers include MySpace, Facebook, Bebo and LinkedIn. But while these may be the heavy-hitters in the Web 2.0 social networking space, they do not represent the only opportunities the Web has to offer.

Directories represent another type of social network that have endured since the days of Web 1.0. People-powered search through directories such as DMOZ has been around for more than a decade, and, despite vast improvements in algorithmic search in the time since their founding, they still play a very vital role in the search world.

But how can search, a seemingly solitary activity, be collaborative? There really are three interdependent social networks that combine to make the whole, and within each these networks, it is the collective knowledge and experience of the community that contributes to the success of the interaction. The three networks include:

1. The end user community
2. The editor community, and
3. The webmaster/site-submitter community

Let's take a closer look at how these work together using as an example a user's query for "eagles." Does the user want information on the West Coast Eagles, an Australian Rules football team? The rock band popular for hits such as Hotel California and Tequila Sunrise? Or does the user want to know more about birds of prey?

An algorithmic engine can make a good guess about the context, but it might not always get it right, especially in cases where the user intends a slightly more obscure result. It is in this type of ambiguous situation, however, where human-powered search can really shine.

If the user turns to a directory to find information about eagles, he or she will be engaging in a dialog of sorts with the editor community. The dialog is not direct, but rather, it is represented by the contextual meaning built into the hand-built category structure. Perhaps the user in our example is actually looking for information on the Fraternal Order of the Eagles, a service organization that operates throughout the and . He or she can simply bypass DMOZ's Sports, Science and Art categories and drill down directly through the Society category to find the desired results.

Behind the scenes, the second social network – the editor community – may have had a lot to do with this users' success. There is a "wisdom of crowds" element within the editor community in which the opinions of many people help to create a clearer directory structure and find better placements for hard to categorize sites than any one editor could do if working alone. Additionally, editors with specific knowledge of a geographic location or subject area may help others to place sites into the appropriate locations within the directory. For example, a new editor may have consulted the community for help to determine whether the Fraternal Order of the Eagles was better suited to be grouped with Clubs & Lodges or Organizations.

Through the final network, the webmasters/site-submitters, thousands of site suggestions are routed to the appropriate editors who sort them to determine if and where they should be included in the directory.