M ASSIVE M ULTIPLAYER O NLINE G AMES —V IRTUAL W ORLDS

Virtual worlds are computer-based simulation environments that allow users to interact via avatars. They are often described as persistent, shared, and computer-moderated environments in which multiple users interact with each other and make changes via individual representations and movements in real time [3]. Due to increased time spent online and greater complexity in online behaviors affecting physical world communication, interpersonal relationships, and communities, virtual worlds are now recognized as real but not concrete [4].

Virtual worlds visually mimic complex physical spaces in which people can interact using self-created avatars as alter egos [5]. Although they have other non-entertainment applications (e.g., education, public policy making, business trades, advertising simulations) [6, 7], most virtual worlds that are the targets of research are game-based [3], mostly text-based Multi-User Dungeons (MUDs) and graph-based Massive Multiplayer Online Games (MMOGs). The immense popularity of MMOGs is reflected in the number of subscribers in 2006: 14,000,000 and growing [8].

Launched in 2003, Second Life is a typical web-based virtual world (Figure 1). Since 2003 it has attracted 13 million “residents,” with up to 50,000 playing at the same time

(http://secondlife.com/whatis/economystats.php). Compared to other MMOGs, Second Life has no clear goals, missions, experience levels, or victories. The main activities are social communication, participation in group activities, and producing/selling virtual objects and services (e.g., virtual building construction, giving music lessons). This and similar games (e.g., ActiveWorlds, Kaneva, and Entropia Universe) blur the boundaries between virtual and

physical worlds—for example, the virtual “Linden Dollar” currency in Second Life can be exchanged for real world currencies (265 Linden Dollars = $1US when this report was being written), virtual Second Life objects have been sold on ebay, and at least one country (Sweden) has created a virtual Second Life embassy to introduce its culture and to canvass visitors.

Another remarkable example of a virtual world is World of Warcraft (WoW) created by Blizzard Entertainment (Figure 2). WoW is currently the world’s most successful MMOG, with

over 10 million players as of January 2008. WoW crosses regional and cultural boundaries, providing services in North America, Europe, and East Asia. Main WoW activities include visiting virtual “zones,” accepting and executing missions, upgrading avatar levels, buying, selling and trading treasure and equipment, and joining guilds. Blizzard continues to develop and distribute expansion packs and game content updates (especially high-end group missions) as part of its major effort to retain players. It is also attracting considerable research attention in terms of its in-game communities, organizations, and player characteristics.

Figure 1. Second Life screenshots. All objects are user-created. Two buildings at the top of the screenshot are embassies, one for the Maldives and one for Sweden. Avatars in central section are involved in an online meeting. Second Life players have the power to design game actions,

including sexual behavior.

Figure 2. World of Warcraft Screenshot. Similar to most other MMOGs, WoW avatars use weapons to win experience points and to earn gold.

The dramatic increase in the number and quality of MMOGs since 1997 has impacted not only the game market, but also multiple aspects of gaming society and culture [9]. The popularity of gaming and the formation of MMOG online/offline communities have resulted in the breaking down of boundaries formed by age, sex, race, and national origin. The rapid increase in the number of online games has resulted in a steady stream of new products developed by a growing number of commercial companies. Designers have increasingly focused on detailed aspects of game societies consisting of player avatars, and the growing number of increasingly sophisticated games is attracting exceptionally high numbers of new players. The average age at which children begin to play video games has fallen at the same time that the number of adults subscribing to online games has sharply increased [10, 11].

As MMOG popularity has grown, players have become more immersed in virtual worlds consisting of game situations and player communities. Individual players spend considerable time, money, ideas, and emotional energy creating avatars and maintaining relationships with each other. Avatars often evolve into identities that players adopt when trading game-based equipment, knowledge, and virtual capital and property. In some cases game capital and property take on value in the physical world, and game achievements, friendships, and appearances take on emotional or personal value. Game-related transactions create second lives for many players [12], leading to a description of online games as a collective “third place” whose status competes with family, work, and school [1]. Compared to other types of virtual worlds, MMOGs attract greater research attention because they cross boundaries between countries and cultures, yet the location of servers in different countries allows for the expression of unique cultural characteristics during play. Accordingly, they allow for studies of hierarchies, societies, organizations, and individuals in both virtual and physical worlds.

MMOGs and online/offline social interactions are drawing considerable attention from players, game developers, and researchers in the computer and social sciences [13]. Topics attracting the greatest research interest include the effects of a player’s social context on choosing games to play, common online and offline resources used to solve problems during initial stages of game play, how experienced players establish new goals and how their

processes that form social norms in virtual societies, how players gain experience and expand their social networks inside and outside the games they play [14], how players form informal communities and highly structured organizations [15], and how players create or design new game content [16]. Today’s players not only come together in the same virtual space to play, but also form offline player communities. Today’s players frequent game websites and discussion boards to share their experiences and to discuss game-related issues.