Online games refer to games that are played over some form of computer network. At the present, this almost always means the Internet or equivalent technology; but games have always used whatever technology was current: modems before the internet, and hard wired terminals before modems. The expansion of online gaming has reflected the overall expansion of computer networks from small local networks to the Internet and the growth of Internet access itself. Online games can range from simple text based games to games incorporating complex graphics and virtual worlds populated by many players simultaneously. Many online games have associated online communities, making online games a form of social activity beyond single player games.
The rising popularity of Flash and Java led to an Internet revolution where websites could utilize streaming video, audio, and a whole new set of user interactivity. When Microsoft began packaging Flash as a pre-installed component of IE, the Internet began to shift from a data/information spectrum to also offer on-demand entertainment. This revolution paved the way for sites to offer games to web surfers. Most online games like World Of Warcraft, Final Fantasy XI, and Lineage II charge a monthly fee to subscribe to their services, while games such as Guild Wars offer an alternative no monthly fee scheme. Many other sites relied on advertising revenues from on-site sponsors, while others, like RuneScape, let people play for free while leaving the players the option of paying, unlocking new content for the members.
After the dot-com bubble burst in 2001, many sites solely relying on advertising revenue dollars faced extreme adversity. Despite the decreasing profitability of online gaming websites, some sites have survived the fluctuating ad market by offsetting the advertising revenue loss by using the content as a cross-promotion tool for driving web visitors to other websites that the company owns.
Early online games
Early networking and timesharing environments often featured games among their most admired features. The CDC Plato system's game gallery was famous, as was Maze War at Xerox PARC. When personal computers reached the general public in the 1980s, simple multiplayer text-based games, MUDs, were often played on BBS systems using a modem. These games were frequently based on fantasy settings, using rules similar to those in the role-playing game Dungeons & Dragons. Other styles of games, such as chess, Scrabble clones, and other board games were available. Since continuous connectivity was often expensive as access was frequently charged on a per-minute basis, some games were set up as play-by-email games.
During the 1990s, online games started to move from a wide variety of LAN protocols (such as IPX) and onto the Internet using the TCP/IP protocol. Doom popularized the concept of deathmatch, where multiple players battle each other head-to-head, as a new form of online game. Since Doom, many first-person shooter games contain online components to allow deathmatch/arena style play.
Real-time strategy games
Early real-time strategy games often allowed multiplayer play over a modem or local network. As the Internet started to grow during the 1990s, software was developed that would allow players to tunnel the LAN protocols used by the games over the Internet. By the late 1990s, most RTS games had native Internet support, allowing players from all over the globe to play with each other. Services were created to allow players to be automatically matched against another player wishing to play.
Cross-platform online play
As consoles are becoming more like computers, online gameplay is expanding. Once online games started crowding the market, open source networks, such as the Playstation 2, Dreamcast, and Gamecube took advantage of online functionality with its PC game counterpart. Games such as Phantasy star Online have private servers that function on multiple consoles. Dreamcast, PC, Macintosh and GameCube players are able to share one server. Earlier games, like 4x4, Quake III and Need for Speed also have a similar function with consoles able to interact with PC users using the same server. Usually a company like Electronic Arts or Sega runs the servers until it becomes inactive, in which private servers with their own DNS number can function. This form of open source networking has a small advantage over the new generation of Sony and Microsoft consoles which customize their servers to the consumer.
The development of web-based graphics technologies such as Flash and Java allowed browser games to become more complex. These games, also known by their related technology as "Flash games" or "Java games", became increasingly popular. Many games originally released in the 1980s, such as Pac-Man and Frogger, were recreated as games that could be played using the Flash plugin on a webpage. Most browser games have limited multiplayer play, often being single player games with a high score list shared amongst all players.
Browser-based pet games are also very popular amongst the younger generation of online gamers. These games range from gigantic games with millions of users, such as Neopets, to smaller and more community-based pet games.
More recent browser-based games use web technologies like AJAX to make more complicated multiplayer interactions possible.