One billion people used Facebook on Monday, according to a (what else) Facebook post by CEO Mark Zuckerberg, who founded the social network in 2004 while he was a student at Harvard. Facebook has 1.18 billion active users per month, but a billion users active on one day is a big deal.
"When we talk about our financials, we use average numbers, but this is different. This was the first time we reached this milestone, and it's just the beginning of connecting the whole world," he wrote. "A more open and connected world is a better world. It brings stronger relationships with those you love, a stronger economy with more opportunities, and a stronger society that reflects all of our values."
Facebook went public in 2012. The stock hit about $90 a share in after-hours trading on Thursday.