by Josh Bernoff

We continually get asked by our corporate clients: why do people participate in social activity online? What drives them?

In Groundswell we tried to collect as many reasons as we could, to reflect the diversity that drives all this participation. In this post I'll list as many as I can. But this is just a start -- participation is as varied as the people who participate.

• Keeping up friendships. Facebook is about connecting with people you know, to find out what's going on with them.
• Making new friends. We've all heard stories of people hooking up on social networks. According to Forrester's consumer surveys, one in five online singles has viewed or participated in online dating in the past year.
• Succumbing to social pressure from existing friends. People in the groundswell want their friends there, too. Your friends, your daughter, or your golf buddies are emailing you right now, asking you to join them.
• Paying it forward. Having seen that a site is useful, you may be moved to contribute.
• The altruistic impulse. This is Flickr cofounder Caterina Fake's "culture of generosity." It's what made Wikipedia possible. People just want to help.
• The prurient impulse. People are sexy, entertaining, and stupid. All that is on display in an endless parade of exhibitionism.
• The creative impulse. If you're a photographer, a writer, or a videographer, the Web is the perfect place to show your work.
• The validation impulse. People who post information on Yahoo! Answers, for example, would like to be seen as knowledgeable experts.
• The affinity impulse. If your bowling league, your PTA, or your fellow Red Sox fans have connected online, you can join and connect with people who share your interests.

Respect this diversity. Keep it in mind as you set up your social applications. Assuming everyone wants the same thing as you do -- or as each other -- is a big mistake.