According to the United Nations, 75 percent of the earth’s population, an estimated 4 billion people, have no address. In regions where this is a particular problem – parts of Africa, the Middle East, South East Asia and Latin America – it can be difficult not only for mailing purposes, but for opening a bank account or reaching someone in an emergency.
Image: Monk's huts in Tigray, Ethiopia. (Credit: Rod Waddington/Flickr)
