Anybody remember charge-a-plates? They worked at most of the department stores sort of like a credit card. I think they were supposed to be paid in full at the end of the month, and possibly each participating store did their own billing. I was too young to be paying bills back then, but I sure did like going into a store with my mom's charge a plate and buying stuff!
Those were the first charge cards and each store had their own. They were made of metal and carried in a little red plastic pouch. They would be placed on a roller machine with a handle that when compressed by force would roll over the charge a plate and the account number would be inked onto the receipt. After running the receipt through the cash register, you would sign. They would charge your account printed on the receipt for the purchase and you would get a bill at the end of the month. The plate was just a piece of metal with your account number raised on it which could be transferred to a receipt with pressure and some ink. It was actually smaller than today's plastic cards.
So THAT'S what "charge-a-plates" were! I remember seeing them referred to once in a "Peanuts" cartoon and I didn't know what they were. (Somebody had put a charge-a-plate in a church offering plate.) A product of the times, I guess.
What I remember more was an earlier form of the Fort Worth Public Library cards. They were plastic, not metal, but your name and address were embossed on them. I think they were the same size as credit cards so that they could be used with those same types of hand-operated roller machines. Each book you wanted to borrow had a stiff plastic card with the book's title, author, etc. embossed on it. When you wanted to check out, the librarian would take your library card, the book's plastic card, and slide them both into the roller machine with a little package of papers and carbons. After sliding the roller back and forth across this whole mess, a paper record was made of your checking out that particular book. (The due date showed up, too, IIRC, being changed every day with a little thumb wheel.) Then the librarian would tear out the carbon sheets (a characteristic sound you'd hear hundreds of times each day in the library), throw them into the trash under the counter, then slide the book's original plastic card and the new paper record back into the book's sleeve on the back page. And you got your card back, too. With a little practice a new librarian could quickly get into the rhythm of doing this and really rip through a whole stack of books in practically no time at all.
I think librarians were supposed to keep track of how many books, LPs, or other items were checked out by category. They had a little mechanical pushbutton counter that they would push, with about five buttons on it, each one of which had its own mechanical numerical counter. They'd push each button several times, according to what you'd just checked out, and how many of each type.
These days the cards are not embossed; they just have a bar code read by a laser scanner, and each book/video/CD has its own bar code number, too, so those hand-roller machines are now probably rusting in a warehouse somehwere. My guess is the librarians don't miss them at all. It's much easier to just pass the book under a laser than to ram that roller machine back and forth hundreds of times a day.
The Arlington Public Library has a system that's even better. Your library card still has a bar code that's read by a laser scanner, but each book/video/CD now has its own RFID chip embedded inside it. This system is so simple to use that now even the library patrons can check stuff out all by themselves by simply placing each book on a little table and the machine reads it automatically. No librarian required.