• Arcade Games: element of real-time video interactivity
• Console Systems: started as games for single players but subsequent generation permitted players to compete against each other
• LAN Games: computer-based instead of console-based, unlimited number of participants
• Internet Connectivity: 90s consoles with compact disks and 32 and 64 bit systems/ 00s ability to connect to the internet, the landscape of video games became more expansive
• Unstructured Games: freedom for the player to roam around a large world, realistic features like the progression of time etc
• Games with Player Generation of Content: near-total freedom to within the gaming environment, player omnipotence, players however, still played a game with online components but did not exist in a virtual world.
• Worlds with Designer-Provided Objectives: avatars can wander where they wish but also gain skills and strengths by earning experience points (MMORPGs)
• Social Networking Sites: not games per se but helped the creation of virtual worlds, profile creation and support of authorized viewers.
• Open Virtual Worlds: social interaction between people and their avatars in 3d immersive environments with user-chosen objectives, user-generated content and social networking tools

References

Messinger, P.R., Stroulia, E., Lyons, K., 2008. A typology of Virtual Worlds: Historical Overview and Future Directions. In Journal of Virtual Worlds Research, Vol. 1, no. 1, “Virtual Worlds Research: Past, Present & Future,” July 2008.

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