A billion people used Facebook in one day for the first time. The boss of Facebook said it was a big achievement. He posted on his Facebook that: "We just passed an important milestone. For the first time ever, one billion people used Facebook in a single day." One in seven people on Earth used Facebook last Monday. The boss said that: "It's just the beginning of connecting the whole world [to bring] stronger relationships with those you love".
Facebook started in 2004. It quickly became one of the biggest sites in the world. It now has 1.5 billion users. That number will grow. In 2012, Facebook had one billion users who used the site once a month or more. Today, the site gets one billion visitors in one day. Facebook must grow in Africa and Asia, where it isn't so popular. Facebook's owner Mark Zuckerberg is the ninth richest person in the world. He is just 31 years old.