How do shops use barcode to keep track of stocks
Answers
If you run a busy store, you need to keep track of all the things you sell so you can make sure the ones your customers want to buy are always in stock. The simplest way of doing that is to walk around the shelves looking for empty spaces and simply refilling where you need to. Alternatively, you could write down what people buy at the checkout, compile a list of all the purchases, and then simply use that to reorder your stock. That's fine for a small store, but what if you're running a giant branch of Wal-Mart with thousands of items on sale? There are many other difficulties of running shops smoothly. If you mark all your items with their prices, and you need to change the prices before you sell the goods, you have to reprice everything. And what about shoplifting? If you see a lot of whisky bottles missing from the shelves, can you really be certain you've sold them all? How do you know if some have been stolen?
Using barcode technology in stores can help to solve all these problems. It lets you keep a centralized record on a computer system that tracks products, prices, and stock levels. You can change prices as often as you like, without having to put new price tags on all your bottles and boxes. You can instantly see when stock levels of certain items are running low and reorder. Because barcode technology is so accurate, you can be reasonably confident that any items that are missing (and don't appear to have been sold) have probably been stolen—and maybe move them to a more secure part of your store or protect them with RFID tags.
A barcode-based stock system like this has three main parts. First, there's a central computer running a database (record system) that keeps a tally of all the products you're selling, who makes it, what each one costs, and how many you have in stock. Second, there are the barcodes printed on all the products. Finally, there's one or more checkout scanners that can read the barcode.
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