My parents had a contact book when I was little (back in the 80s), but they eventually went to a system of cards standing up in a tray separated by last letter.

My parents had a contact book when I was little (back in the 80s), but they eventually went to a system of cards standing up in a tray separated by last letter. It made it easy to pull it out when you wanted to make a call. They now have a mixed system where their most used phone numbers are in their iPhone contacts, but they have still have that tray for everybody else. I had a contacts section in my DayTimer back in the 90s, but I've used a contacts program ever since I switched to using a computer-based calendar.