The global number of Internet users has surpassed one billion with China accounting for the largest population of Web surfers, digital research firm comScore reported on Friday.

"Surpassing one billion global users is a significant landmark in the history of the Internet," comScore chief executive Magid Abraham said in a statement. "It is a monument to the increasingly unified global community in which we live and reminds us that the world truly is becoming more flat," Abraham said. "The second billion will be online before we know it, and the third billion will arrive even faster than that," he said.

ComScore said the total number of Internet users had surpassed one billion in December. The actual number of Web surfers is probably higher than that as comScore said its figures were based only on the number of Internet users aged 15 and above working from home or work computers. They did not take into account traffic from public computers such as Internet cafes or access from mobile phones or personal digital assistants.

The Asia-Pacific region accounted for the highest share of global Internet users at 41 percent, followed by Europe (28 percent share), North America (18 percent share), Latin-America (7 percent share), and the Middle East & Africa (5 percent share).

China represented the largest online audience in the world in December 2008 with 180 million Internet users, representing nearly 18 percent of the total worldwide Internet audience, followed by the U.S. (16.2 percent share), Japan (6.0 percent share), Germany (3.7 percent share) and the U.K. (3.6 percent share).

The most popular property in the world in December was Google Sites, with 777.9 million visitors, followed by Microsoft Sites (647.9 million visitors), Yahoo! Sites (562.6 million visitors). Facebook.com, which has grown a dramatic 127-percent in the past year to 222 million visitors, now ranks as the top social networking site worldwide and the seventh most popular property in the world.