Just to put this in perspective: Population of USA is about 300 million and Europe is about is 740 million. Together it is slight above 1 Billion, but Facebook

Just to put this in perspective: Population of USA is about 300 million and Europe is about is 740 million. Together it is slight above 1 Billion, but Facebook had 1 Billion unique visitors in 1 day! That is just mind-boggiling.