A lot of people have been speculating about what makes a site “Web2.0” and I have been putting together my own conception of it. I think that what is different about Web2.0 sites is not necessarily the content, AJAX, novelty, domain names with dots everywhere, or rounded corners and gradients. Instead, the most successful candidates are (a) extremely supportive of the two main purposes of interacting with the web and (b) incorporate two new factors that don’t exist on pre-Web2.0 sites.

The two behaviors people exhibit when going on-line are either gathering information from or contributing information to the web. Gathering is both searching for information and storing it so that you may find it again later. It is a selfish thing, all about consuming and using info for your own needs. Contributing is about actions such as blogging, participating in forums, commenting, collaborative filtering, and sharing content like photos and videos. It’s all producing and sociality.

I made the suggestion a while ago that Google = Information and Yahoo = Community, but you could also interpret that as Google = Gathering and Yahoo = Contributing. I ran across another Google/Yahoo comparison that implied that gathering and contributing are opposing behaviors and there is even a gender bias for one over the other. In my opinion the gender difference is mainly in which behavior you believe will benefit you the most on a personal level.

But, the behaviors are not exclusive of each other. I believe that they are flip sides of a coin and the best sites support them both at the same time. Useful pre-Web2.0 sites (such as Google and Yahoo) already cater to these behaviors in various degrees, but that’s just not enough. What makes a site Web2.0 is two factors that have really been the catalysts for the changes in our expectations of interaction with a service on the web: Metadata and Portability.

Metadata is the first Web2.0 effect. It makes a community out of selfish individuals by combining the benefits of gathering and contributing. By allowing you as an individual to organize information to make it easier for you to rediscover later, the contribution of metadata supports gathering with the useful side-effect of being beneficial to the you as a community member as a way to discover new information. It is a positive feedback loop that becomes a personal boon very quickly.

Or as Alex Barnett put it:

Personal value >> Network effects >> Personal value

And Joshua Schachter:

You’re doing it for yourself, but the good of the group. Delicious is about memory first, discovery second.

Portability is the second Web2.0 effect. Web1.0 sites are walled off and not extensible. Their content stays on their site and under their organization scheme. But content is portable, re-mixable and customizable in the new web. The term Web2.0 began to float around when sites popped up that supported metadata as a means for organizing and sharing as well as giving users the means to pull their content out of the site and repackage it. These sites either made it easy to apply metadata to your contributions or made the metadata core to the experience and provided one or several ways to re-consume your data through feeds and open APIs. Prime examples, of course, are Flickr and Del.icio.us. Both are successful because, even though they started with the selfish purposes of organizing personal information, they fostered very functional and useful communities because of their metadata and APIs.

I believe that to be successful under the expectations we all have now for our experience with Web2.0 any new site or web service must absolutely support both gathering and contributing by giving users the ability to create metadata and providing content portability. Or, at the very least, the site must compliment a service that is lacking in one or the other by providing the missing factor. If you’re not doing that, you’re not Web2.0!