A virtual world is a computer-based simulated environment intended for its users to inhabit and interact via avatars. These avatars are usually depicted as textual, two-dimensional, or three-dimensional graphical representations, although other forms are possible (auditory and touch sensations for example). Some, but not all, virtual worlds allow for multiple users.

The computer accesses a computer-simulated world and presents perceptual stimuli to the user, who in turn can manipulate elements of the modeled world and thus experiences telepresence to a certain degree. Such modeled worlds may appear similar to the real world or instead depict fantasy worlds. The model world may simulate rules based on the real world or some hybrid fantasy world. Example rules are gravity, topography, locomotion, real-time actions, and communication. Communication between users has ranged from text, graphical icons, visual gesture, sound, and rarely, forms using touch and balance senses.

Massively multiplayer online games commonly depict a world very similar to the real world, with real world rules and real-time actions, and communication. Communication is usually textual, with real-time voice communication using VOIP also possible.

Virtual worlds are not limited to games but, depending on the degree of immediacy presented, can encompass computer conferencing and text based chatrooms. Sometimes, emoticons or 'smilies' are available, to show feeling or facial expression. Emoticons often have a keyboard shortcut.

History

The concept of virtual worlds predates computers and could be traced in some sense to Pliny.

Maze War (also known as The Maze Game, Maze Wars or simply Maze) was the first networked, 3D multi-user first person shooter game. Maze first brought us the concept of online players as eyeball "avatars" chasing each other around in a maze.” (http://www.digibarn.com/history/04-VCF7-MazeWar/index.html, 29th Feb). According to the website this was in 1974, it was played on Arpanet (the initial internet), however it could only be played on an Imlac, as it was specifically built for this type of computer.

Then in 1978 MUD was released, it however was not 3D, it was text-based and used a TELNET program, by following the link you will be able to play the game, and understand just how far virtual worlds have come since http://www.british-legends.com/. You can understandably argue whether or not this is a “virtual world” and that Maze War was more sophisticated (being 3D), but you must understand that MUD could be played by anyone, Maze War was computer specific. Perhaps in today's senses it is not a true virtual world, but the idea of a virtual world in those days were different (see Neuromancer link in bibliography for more information).