Postcards have been printed, sold, mailed, and received on a scale that makes them, historically, the largest class of artifacts that humankind has ever exchanged. There are a lot of different ways to dig into the history of postcards and any history will inevitably be incomplete. Although postcards were a mass medium, they were--and still are--a disposable one. This disposability means that there are holes in the historical record, making a complete archive of all the world's postcards inherently impossible. Many histories of postcards opt to explore postcards through specific pictorial or geographic themes ("historic postcards of New York City") or printed types ("American holiday postcards.") These narrow, specific approaches tend to focus on postcards by a particular manufacturer, such as the iconic Curt Teich & Co. Americana postcards or the carefully lithographed portraits found on cards by London printer Raphael Tuck & Sons. Others opt to concentrate on specific postcard technologies, like Kodak's "real picture" postcards. As many types and styles as there are of postcards, there is an equal number of ways to talk about their histories. Throughout this project, I've learned at first hand that postcards are personal and always have been. I didn't start out to write a book that drew so heavily from collections of family postcards or to highlight my own different postcard experiences. But, completely unexpectedly, the medium lent itself to this approach, as postcards require us to recognize that global social networks are built out of individual stories and connections. The more I dug into stories about postcards, the more I found myself and my family in them. For example, my own great-grandfather, Robert Boles, saved a shoebox full of hundreds of postcards that were sent to him between 1905 and 1920--what historians call the Golden Age of Postcards. His daughter, my grandmother, kept the cards for years and gave them to my mom, who has long been interested in family history from my dad's side of the family. My mom bequeathed the postcards to me when I started the background research for Postcards, convinced that these family mementos would offer a way to humanize the global postcard phenomenon. She was right. To that end, reading postcards in various libraries and archives felt a bit as though I was reading messages in bottles; I didn't know the recipient or the sender, and the message on the back would have made sense only to them. To put it another way, it was like reading a stranger's text messages and trying to figure out the backstory for any individual text. Drawing on postcards from my family's collection meant that I "knew" the people writing, receiving, or saving the postcards in a way that I couldn't with postcards from other institutional collections. It continued to make postcards personal. Postcards have left an indelible imprint on the history of human communication, unmatched by any other material medium. They owe their success to the decentralization of their manufacture as well as the physical material connection they created between sender and recipient. Postcards and their digital descendants continue to be about personal connections--specifically, short, cheap, ephemeral messages. There are inexorable echoes of postcards in contemporary digital picture networks such as Instagram, Twitter, Facebook, Snapchat, TikTok, and other photo-sharing apps. We recreate old social networks--old postcard social lines, if you will--with every post of a digital picture. Postcards are not yet completely extinct. Excerpted from Postcards: The Rise and Fall of the World's First Social Network by Lydia Pyne All rights reserved by the original copyright owners. Excerpts are provided for display purposes only and may not be reproduced, reprinted or distributed without the written permission of the publisher.