"In addition to sharing and connecting with friends, people are engaging in real time with the media and the public voices they care about most."
Facebook is the latest social media company to capitalize on TV-related traffic around big events like the World Cup, a trend started years ago by the microblog website Twitter Inc.
People use Facebook to comment about things they watch live, an interaction that could turn into a source of ad revenue for the company.
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Facebook's record numbers were possible because of widespread mobile penetration. Seven out of 10 users globally connect to the network from mobile devices, which represent roughly 60 percent of the company's ad revenue.
There is also soccer's global appeal. The first week of the World Cup alone saw 459 million interactions on Facebook, more than this year's Super Bowl, the Sochi Winter Olympic Games and the Academy Awards combined.
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The 1 billion mark was reached after traffic accelerated as the World Cup moved into the knockout round. On Saturday, more than 31 million people put up 75 million posts, likes and comments about Brazil's nail-biting victory over Chile, which propelled the home team to the quarter-finals.
"This Cup has been a catalyzing cultural moment for people around the world," Grudin said, "and we see it reflected on Facebook."