原虫布丁格

Spectacular growth in online social gaming is prompting companies such as Google to enter the market and developers to rethink how they design video games.

The trend is seeing the social network Facebook emerge as the world's biggest gaming platform. It is closing on 200m active members and its most popular application installed by users is a game - Texas Hold 'em Poker - played by 11m people.

Pet Society , where players create pets and their homes and exercise and care for them with friends, is even more popular in terms of daily players. It has 9m players, with more than 60 per cent of them returning every day to look after their creatures.

The leading publishers on Facebook are San Francisco's Zynga and London-based Playfish, which developed Pet Society and has attracted 60m players to its games in 18 months.

Kristian Segerstråle, chief executive of Playfish, says social gaming is more like the social interactions around kicking a ball in a park than the experience of a traditional console video game.

"The emotional driver for you to play is not the kind of fight or flight emotions which tend to happen between you and the screen on consoles, but the much more powerful emotions of you and your real world friends," Mr Segerstråle says.

"It can be competition, cooperation, expression, communication, just like in real world games."

Social gaming was a hot topic at last month's Game Developers Conference in San Francisco.

"The biggest shift is that, in the past, most of the social gaming has been with people that you don't know. With Facebook that's completely changed," says Brian Fargo, a game developer.

He describes a bowling game on Facebook where he can see his friends and their high scores.

"I want to play now because I want to beat them. The social dynamic of knowing the people out there really changes things for me," Mr Fargo says.

Online gaming on services such as Microsoft's Xbox Live, which has 17m members worldwide, or PC casual gaming destinations such as Pogo or Big Fish generally takes place between strangers.

Facebook is not charging developers for games, mainly because they are initially free and the service is focused on expanding its user base.