Over one billion people used Facebook last Monday. This is the first time the site has had this many visitors at for in of on with one day. The CEO at for in of on with Facebook, Mark Zuckerberg, said it was an important achievement at for in of on with his company. He posted at for in of on with his own Facebook profile that: "We just passed an important milestone. at for in of on with the first time ever, one billion people used Facebook at for in of on with a single day." He said that at for in of on with Monday, "one at for in of on with seven people at for in of on with Earth used Facebook to connect with their friends and family". He added that: "This was the first time we reached this milestone, and it's just the beginning at for in of on with connecting the whole world." Mr Zuckerberg also said a connected world, "brings stronger relationships at for in of on with those you love". Zuckerberg created Facebook at for in of on with 2004, while he was a student at for in of on with Harvard University. The website quickly became one at for in of on with the biggest sites at for in of on with the world. Today, it has nearly 1.5 billion users and Zuckerberg thinks that number will grow. at for in of on with October 2012, he announced that Facebook had one billion users who used the site at for in of on with least once a month. Three years later, the site had one billion visitors at for in of on with just one day. Zuckerberg said the company needs to grow a lot at for in of on with countries where Facebook isn't so popular, such as at for in of on with many African and Asian countries and some at for in of on with Central and South America. Facebook has made Zuckerberg the ninth richest person in the world, at for in of on with the age of 31.