Abstract Keywords: virtual worlds, typology, continuum, game space.  By Jeremiah Spence, Department of Radio, TV & Film, University of Texas at Austin. Virtual worlds, as both a concept and an industry, have changed radically over the past ten years, from a toy for the technological elite to an over-hyped marketing phenomenon, and with this radical change comes the need for reexamining the uses and utility of virtual world technologies and experiences. This paper offers such a reexamination. Within academia in particular there are a number of issues that require further examination. The academic community appears to be divided into four camps: 1) those who embrace virtual worlds; 2) those who have ignored the evolving use of this technology; 3) those who are aware of but have not yet explored the technology; and 4) those who are entirely unaware that virtual worlds exist. Among those who study virtual worlds there is an overwhelming focus in terms of research, publications, and funding on a single one of these worlds, Second Life, which serves only a fraction of the entire population utilizing virtual worlds or similar technologies. An overview of the size, shape, and forms of virtual worlds may help with both of these issues, the ignorance of virtual worlds among some researchers and the overwhelming focus on a single example among others. In the broadest terms a virtual world can be conceptualized as "a place described by words or projected through pictures which create a space in the imagination, real enough that you can feel you are inside of it" (Damer, 2008) . In this sense, a virtual world can be thought of as anything from the painted caves of our ancestors or shadow puppetry to such literary worlds as Dante's Inferno (Bittarello, 2008), Eco's monasteries (1983), Shakespeare's tragedies, Japanese samurai stories, Orson Welles' radio enactment of The War of the Worlds (1938), and the Wachowski brothers' Matrix movies. The computer, by mediating the experience of communication and interaction with large quantities of information, makes it possible to expand the relationship between the imaginary and the real into a persistent three dimensional space. In his novel Snow Crash Stephenson (1992) provided one of the defining depictions of a non-game virtual world with Hiro Protagonist's exploits in the metaverse, a term that the novel introduced into the public discourse. Stephenson's metaverse is a three-dimensional virtual world where users interact with each other via avatars and through immersive technology; the users in this metaverse are able to experience and interact from a first-person perspective. The concept of the metaverse as laid out by Stephenson in his fictional work has proved instrumental in providing a vision for real-world computer programmers and technologists to emulate in their development of a variety of new virtual worlds, from SnowMoo, Active Worlds, There, and Second Life to Croquet and Google Lively. Building on the metaverse vision presented in Snow Crash, technologists developed a Metaverse Roadmap that presented a "ten-year forecast and visioning survey of 3D Web technologies, applications, markets, and potential social impacts [… including] the convergence of Web applications with networked computer games and virtual worlds, the use of 3D creation and animation tools in virtual environments, digital mapping, artificial life, and the underlying trends in hardware, software, connectivity, business innovation, and social adoption that will Although no single definition of virtual worlds exists, scholars continue to explore the key factors that separate virtual worlds from non-virtual worlds. Before discussing those factors, a distinction must first be made between game space and non-game space. A game can be understood as a "multi-agent interactive representation of subjective reality that defines a problem space with which the player can act as a solution explorer within the bounds of the space," (Hypography, 2007) . Game space is a three-dimensional computer simulation that integrates elements of game into a persistent online massively multiplayer environment. Online games and online game spaces can be separated into two categories, those that are persistent and those that are not persistent. Persistence in this context refers to games and online game spaces that continue to exist when the user is not logged in, in contrast to the older style of computer games that stop when a user logs out. Contemporary examples of game space are the online worlds associated with World of Warcraft, Eve Online, and Ultima, among many others. The concept of a virtual worlds can be distinguished from the concept of game space by the absence of the characteristics of a "game." Bell (2008) presents a number of previously proposed definitions of a virtual world and proposes a synthesized, more contemporary definition that attempts to take into account changes that have appeared in virtual worlds over the past several years (Chesebro, 1985; Bartle, 2003; Koster, 2004; Castronova, 2004) . Bell states that a virtual world can be defined as "a synchronous, persistent network of people, represented as avatars, facilitated by networked computers" (2008, p. 1). Bell's definition has three key components: 1. "synchronous" indicates that shared activities necessitate synchronous or real-time communication 2. "persistent," as explained previously, indicates that a "virtual world cannot be paused" or does not shutdown when the user exits 3. the "avatar" is "any digital representation (graphical or textual), beyond a simple label or name, that has agency (an ability to perform actions) and is controlled by a human agent in real time" (2008, p. 1). Schroeder emphasizes the experiential element of virtual worlds. Schroeder defines a virtual environment or, equivalently, a virtual reality as "a computer-generated display that allows or compels the user (or users) to have a sense of being present in an environment other than the one they are actually in, and to interact with that environment" (Schroeder, 1996, p. 25). The collaborative, multi-user element of virtual environments can be described as "environments or systems [in] which users experience other participants as being present in the same environment and interacting with them -or 'being there together'" (Schroeder, 2006; 2008, p. 1). How then does one differentiate between virtual reality or virtual environments and virtual worlds? Schroeder uses the term virtual worlds to refer to "persistent online social spaces," which, however, leaves one with the problem of differentiating between virtual worlds, as presented in this definition, and online game spaces (Schroeder, 2008) . Researchers have noted an increasing degree of socialization taking place in persistent online game spaces, such as World of Warcraft, which brings them closer to Schroeder's definition of a virtual world; still, The distinction centers on the emphasis on the social nature of virtual worlds without the "game" elements as the primary defining rules of the space. To state the distinction in another way: Games can exist in virtual worlds, but virtual worlds are not game spaces -they are social spaces. Frequently virtual worlds are described as serving the function of a third place or third space, referring to a public space where one shares leisure and social spaces with other people but that is neither home nor work. The third place is similar to the city square, town plaza, coffee shop, hang-outs, or salons of other eras (Oldenburg, 1991; 2000; Steinkuehler & Williams, 2006) . Oldenburg (1989) explains that "third places exist on neutral ground and serve to level their guests to a condition of social equality. Within these places, conversation is the primary activity and the major vehicle for the display and appreciation of human personality and individuality" (p. 89) The connection between virtual worlds and the third place frequently reinforces the educational process (Bruckman & Resnick, 1993; Schwienhorst, 1998) . The connection between the third place and online game spaces, such as World of Warcraft, has been extensively studied (Steinkuehler, 2005; Steinkuehler & Williams, 2006; Wadley, Gibbs, Hew, & Graham, 2003) . Although some have attempted to expand the term third place to include all forms of computer-mediated communication (Soukup, 2006) , the concept, as outlined by Oldenburg, applies directly to social virtual worlds. Virtual worlds are places of neutral ground and foster a certain degree of social equality, where one might pursue conversation, content creation, and the exchange of the goods Tracing the development of virtual reality from the Sensorama simulator of 1962 to contemporary virtual modeling systems built on Silicon Graphics computers, Burdea and Coiffet define virtual reality as a high-end user computer interface that involves real time simulation and interactions through the visual, auditory, tactile, smell and taste senses (2003). The development of virtual reality technologies focuses on the three "I's": to feel the reality through immersion, to change and modify the reality through interaction, and to extend the function of the reality through imagination (Burdea and Coiffet, 2003) . Sivan sees the development of gaming worlds as the second component in the marriage of technologies that spurred the development of virtual worlds. Tracing a lineage from the first multi-user dungeons (MUDs) in the late 1970s to World of Warcraft and its contemporaries today, one finds that these increasingly complex gaming worlds provided the foundation for the development of the social aspect of virtual worlds (Sivan, 2008, p. 3; Bartle, 2004; Morningstar & Farmer, 1991; Taylor, 2006; Alexander, 2003; . Sivan describes real virtual worlds as depending on four elements: 3D (threedimensionality), community, creation, and commerce, which collectively are referred to as 3D3C. In addition to placing three-dimensionality at the core what defines a real virtual world, the concept of 3D3C emphasizes the social nature of virtual worlds and the roles that content and commerce serve in reinforcing the integrity and cohesiveness of a real virtual world (Sivan, 2008) . Journal of Virtual Worlds Research -Demographics of Virtual Worlds 5 5 Obtaining accurate data on the size and shape of the universe of virtual worlds can be a complicated task, as most commercial virtual worlds consider their user data to be a trade secret. This leaves the researcher dependent mainly on data from press releases or consulting firms, which may or may not be accurate. Even obtaining a baseline of the total population of current registered users of commercial virtual worlds is a challenging task; the most frequently cited number is 300 million registered users (Hays, 2008) . This is not the same as the total number of regular or current users, which is considered by most companies to be a trade secret and which is suspected to be considerably less than total number of registered users. Building upon this foundation, this paper will use the following definition: Virtual worlds are persistent, synthetic, three dimensional, non-game centric space. Virtual worlds are primarily social spaces that allow for other uses depending on the theme of the particular virtual world. Virtual worlds are either commercial or open source in design and implementation. This definition characterizes virtual worlds as a distinct phenomenon, separate from MUDs; Massively Multiplayer Online Role Playing Games (MMORPGs), such as World of Warcraft, EverQuest, Eve Online; or other types three-dimensional online game spaces. Game spaces are virtual environments defined by their purpose of pursuing the objectives of a game. Games have rules, levels, and, ideally, a conclusion where the objectives of the game have been achieved (Hypography, 2008) . Virtual worlds, by contrast, are not defined by the rules and goals of a particular game but instead are frequently focused around socialization and content creation. This is not meant to imply that MMORPGs do not have non-game activities taking place, such as socialization and commerce, but in a gaming world the primary function of the virtual environment is to facilitate the achievement of the objectives of the game. Similarly, game playing often takes place within a virtual world, but virtual worlds have many other activities taking place simultaneously which are generally as important as or more important than any game playing. These other activities include education, collaboration, support groups, sexual encounters, and content creation, among numerous other uses. In a virtual world, the user can easily stop gaming and, say, attend a university lecture or visit a nightclub. The framing of virtual worlds as being persistent, synthetic, and three-dimensional delineates virtual worlds from pre-three dimensional online virtual worlds, imaginary worlds, or literary worlds. As the virtual worlds industry grows and becomes more sophisticated, the industry is becoming more segmented, and a number of specific focuses-beyond the basic focus on socialization and content creation-are developing. In order to obtain a clearer picture of the metaverse, this paper examines both primary and secondary data regarding the various types of virtual worlds-or things sometimes referred to as virtual worlds-that are in existence. The paper also documents and analyzes secondary data on the sizes and target audiences of the various virtual worlds. The secondary data source comes from the Universe and Radar graphics of the KZero Consultancy (2008aConsultancy ( , 2008b, which can be found in Appendix 2. It provide a solid point of origin for exploring the metaverse, Journal of Virtual Worlds Research -Demographics of Virtual Worlds 6 6 offering general data on target audiences, sectors of focus, and supposed number of registered users for over 90 "virtual worlds" as classified by KZero. The original research presented here, building upon the foundation of KZero, involved visiting the websites of 112 "virtual worlds," classifying them according to a macro-typology developed for this purpose, identifying the geographical location of each project, and, where possible, attempting to verify the population numbers for the different sites. Commercial virtual worlds are rapidly growing both in size and sophistication as developers, investors, and marketing professionals develop increasingly refined and focused business models for monetizing virtual worlds. Increasingly the lines are being blurred between virtual worlds, as defined here, and other technologies. Game designers are finding that virtual worlds models are useful for increasing the amount of time user spend within the game space. Virtual world designers are using gaming design technology to create increasingly sophisticated user experiences. Entrepreneurs and technologists continue to experiment with the integration of virtual worlds technology with other Internet technologies, such as instant messaging, group collaboration tools, and social networking sites (SNS), such as Facebook, MySpace, or Orkut. As previously explained, the term virtual worlds has been used to refer to a large variety of very different creations. Using the above definition of a virtual world, the survey undertaken for this project found that of the 112 projects evaluated only 41 (or 37% of the total) could clearly be classified as a virtual world. Additionally, 10% of the sample were clearly games -the companies classify the projects as games, they use gaming terminology, and so on. That leaves the remaining 50% of the sample up in the air: How should they be classified if they are neither games nor virtual worlds? To classify these remaining projects, it is useful to introduce the concept of a technological hybrid. This is analogous to the concepts of cultural, racial, and global hybridity (Bhabha, 1994; Garcia Canclini, 1995; Young, 1995) used by other authors in other contexts. Generally speaking, the value of using the concept of hybridity in all these contexts is the same: It provides the necessary heuristic response to an over-simplified dichotomous distinction. In this case, the remaining 50% of the projects fall within a hybrid technological space which can be visualized as existing on a continuum between virtual worlds and game space. The linear continuum from virtual worlds to game space includes 95% of the projects surveyed; however, some of the most fascinating projects using some elements of virtual worlds technology fall outside this continuum. The 5% of the projects that did not fit along the continuum have been classified here as either Chat-Virtual Worlds Hybrids or Non-Persistent Virtual World Spaces (VW-NPS). One example of a chat-vw hybrid is IMVU, which allows a user to enter a chat room with an avatar to interact with another user. IMVU can be compared to instant messaging with a visual element. Non-persistent virtual world spaces are best illustrated by the example of Qwaq, which provides a virtual world space specifically for business meetings or group collaborations. The space is created for the purpose of the encounter, and then, after the encounter is over, it shuts down. The settings and accrued content are saved, and when the space is needed for another meeting the settings and content are retrieved. Given this breakdown of the projects surveyed, this paper will not pretend to give accurate demographics for the games category, as the category would inevitably include the large multitude of MMORPGs and similar game spaces that exist. All projects/sites examined in this survey can be found in Appendix 1. The following frequency tables provide a summary of the demographics of non-game virtual worlds and virtual worlds related projects.
According to REF , a virtual world is a "persistent, synthetic, three dimensional, non-game centric space"; making a distinction between games and social spaces.
Demographics of Virtual Worlds
The Journal of Virtual Worlds Research
Sociology