It all adds up

The supermarket looks like any other. But its checkout stands are a bit unusual. More and more stores of all types are using the new checkout system. This system uses a machine that can do all sorts of things. It can do math you can’t do in your head.

What does the cashier do? He or she simply pulls the food across a small window. The window is at the end of the checkout counter. On the side of the can or box or package is a row of light and dark lines. The lines have numbers. The checkout machine “reads” these lines and numbers when the item is passed across the window. The machine finds out what the item is and sends that message to the computer.

What do those strange lines and numbers mean? The lines help the machine find where the beginning, middle and end of the numbers are. The numbers describe the item for the computer. For example, look at the can. The little 0 on the left means the item came in a package or can of some kind. The first five numbers at the bottom stand for the company that made the item. The last five stand for the name and size of the item.

The computer knows all sorts of information about the item. The computer chooses the facts that might be needed and sends them back to the checkout machine. The machine flashes the name of the item and the price on a small screen and adds the price of that item to the customer’s bill. Then the bill comes out of the machine on a long paper tape.

What else can this wonderful machine do? It can read the weight of a bag of fruit on a scale, figure out the cost and add it to the bill. That’s not all. The computer constantly gets information on which items are purchased and how fast they sell. It lets the store manager know when the store is running out of certain things. The manager can tell how many shoppers there were in the store at any time of the day.

It all adds up. Nowadays almost supermarkets use this speedy checkout system.