An online virtual world that has become one of the web's most popular activities is also becoming an increasingly popular venue for teaching and socialization among educators and youth organizations.

The program, called Second Life, which first opened to the public in 2003, immerses participants in a virtual world of their own making. By setting up an account (either paid or free), users are able to create a virtual persona known as an avatar, which they can personalize to look however they want.

The program, from San Francisco-based company Linden Lab, allows users to create everything within their virtual world. Users are able to buy and sell plots of land, objects they have created themselves, and so on. The world itself and its economy closely resemble that of the "first life," as some in the virtual community call everyday society. In fact, hundreds of thousands of real dollars change hands in Second Life daily, and it would have an annual gross domestic product of around $150 million if it were to stop growing today.

Whatever Second Life is, it's clear that it belongs in a different class than the virtual realities of film and fiction that have gone before it. The closest comparison would be to online video games such as "World of Warcraft" or "The Sims Online." Users download free software that opens a portal to Second Life, and Linden Lab's servers draft models of the ever-changing world and send it back to users as a real-time video. The difference is, Second Life is not a game. It doesn 't have a goal, and most resources aren't restricted. Characters can fly or breathe water, and they never age or die.

With the popularity of Second Life soaring (more than 1.2 million people have joined throughout the world as of press time), it was only natural that educators would take notice of the phenomenon and begin exploring the possibilities of turning it into an educational tool.

Linden Lab has been encouraging educators to take advantage of the multimedia and social-networking possibilities within its program. A year ago, an eMail list was started for educators interested in using Second Life. Within the year, the list has grown to more than 700 educators around the world. In addition, Linden Lab offers the purchase of private islands at discounted rates to educators and nonprofit organizations. If educators want to test out Second Life for a class, Linden Lab will even offer them a free piece of land for the duration of the class. Small private islands are sold for $980, as well as a monthly land fee of $150.

A main draw for educators in using Second Life is the improvement in interaction and expression when compared with programs such as distance-education courses. "I think that is one of the things that's so attractive to educators using Second Life," says Linden Lab community developer Claudia L'Amoreaux, or Claudia Linden as she is known within Second Life. "The quality of interaction is hard to even describe. It doesn 't replace face to face, but it does enable working with people all over the world."