As of 2015, there are over 4.3 billion email accounts, among them 1 billion business mail accounts. 100 billion emails are sent and received per day, in a world containing "only" 7 billion people. If you exclude the 4.4 billion citizens of the world who aren't connected to the internet, the statistics are still astonishing. The power of email has already reached a peak level that seems incomparable, and although the numbers keep growing, the alternatives to email are also finding their ways to the desktops and smartphones of those who are online.