My mom talked about it later and said, "Remember when I used to have to draw all the cows?"
We used to have registered Guernsey cows. Part of their registration papers included a blank cow picture and my mom would draw their markings on. Both sides and the front of their faces. It seemed like it always took a long time to sketch all those cows and get their markings! It worked, regardless.
Other farmers register their cattle, and of course they take digital pictures for their papers. It's just another one of those things I'll tell my grandchildren about. We used to have phones that hooked to the walls, and we had a party line! We used card catalogs in libraries! The internet didn't exist when I was born! And ... grandma used to draw the cattle's markings to identify them!
They won't know what I'm talking about, of course. They'll be too busy on their iPhone 7000.