Buying a Shirt

Let's say you want to buy a shirt...

Go to the local department store and find a shirt that you like with the disinterested assistance of a store employee. The store employee then takes you to a counter in the shirt department and prints out a computerized ticket that includes the shirt description and the price of the shirt. She keeps the shirt and gives you the ticket.

You take this ticket to a counter at the exit, wait in line for your turn, and pay for the shirt. You get a cash register receipt for your payment - but not the shirt. The store employee that originally helped you has taken the shirt to a counter on the opposite side of the exit from where you are standing and has given it to an employee there.

You then take the cash register receipt that you just received to the counter across the doorway, wait in line behind the same people as at the previous counter, and when you get to the front of the line they have your shirt for you. They match up your receipt with the shirt, put the shirt in a bag, and hand it over.

You leave the store with your shirt.

Simple.