#28: The Way to Avoid Overbooking Airline Reservations, 1945

The content depicted in this photo may not be immediately apparent to those of us who are well and truly immersed in the digital age, but what this picture actually depicts is the early process of manually booking airline tickets, with the chart on the wall showing occupied and available seats.

While the system itself is something most of us have probably never seen before and deserves to be marveled at, I have to mention that, in my opinion, the real wonder of this photo is that once upon a time, airlines cared about not double-booking tickets for their flights.