We hear a lot about virtual worlds today as applications like Second Life become more popular. But, as with many evolving concepts, the meaning of the term 'virtual world' can be unclear and confusing. Let's begin with a simple definition, look at the elements of that definition and work up from that.
A virtual world is a shared, modifiable, persistent space made possible through the use of computer and network technology. The first criterion that the virtual world be shared says that a single user video game does not qualify as a virtual world no matter how rich the graphics are nor how complex the narrative may be. You have to have other users in there to interact with. And while it is not explicitly stated, you must interact with the other users in real time. So, if you friends could log in some kind of bot or scripted intelligent agent and then go off and take a nap, it probably would not qualify as a virtual world. There is something about the experience of interacting with other people that is central to the virtual world.
The second criterion is that the world be modifiable. That is,the users interact not only with each other but they interact with the world and change it and/or themselves in some non trivial way. A basic chat room would qualify as a shared space and would certainly meet the real time interaction requirement. But the chat room is not modifiable in any important way. So, it would not qualify as a virtual world. Now, if the chat room were modifiable, say users could define hot keys and write scripts to invoke based on those hot keys, then it may be considered a minimal virtual world.
Next, the changes made to the world must persist after the users logs off. So, let's say that some users entered a shared computer space for a meeting and interacted in real time through voice and text chat. But when the meeting was over, the space was wiped clean for the next user. This would not be considered a virtual world because the changes would not persist from one session to the next.
Finally, the virtual world must be supported by computer and network technology. A shared white board upon with users would write and draw and which would never be erased might qualify as a virtual world otherwise. But clearly the technological support adds some important element.
So, is this definition of a virtual world adequate? Not really. If this definition were adequate then social interaction technologies like Facebook would qualify as virtual worlds. Although Facebook is a wonderful technology, it does not seem to qualify as a virtual world. In the next entry, we will look further to find an adequate definition.