In the beginning, people stored addresses, telephone numbers, and dates in little books. Sometimes called organizers. These paper books were popular and some became fashion statements. A particularly famous one was the luxurious, leather-bound Filofax. In the 1980s, new technologies enabled the rise of a new category of electronic tools to replace those books. Those devices' innovations take us right into the modern era of smartphones. In this sprawling, globe-spanning video, we look at the Personal Digital Assistant, the PDA.