Barcodes. Why do barcodes have the thick and thin lines and numbers on them. Also, why are lasers used to scan them?
In: 0
Barcodes date back to when smart image recognition was beyond the capabilities of cheap personal/company computers.
The numbers written under the barcode are for us humans to read.
The bars themselves represent the numbers in an easily machine-readable form. Think of a barcode as being something like morse code – each pattern of black lines and spaces represents a particular number:
https://en.wikipedia.org/wiki/Universal_Product_Code#Encoding
A laser scanner is typically used for reading because it’s simple… instead of using an entire photographic sensor, the scanner just has to shoot a laser beam at the code and then use a single “photo diode” to read back whether it’s seeing light or dark at any particular moment and to decode those patterns of light and dark back to their corresponding numbers.
Okay, so what do those numbers mean? Well, that depends on context. Barcodes are used in a lot of places, not just in stores. They’re also used in warehouses and shipping hubs and manufacturing processes. For simplicity’s sake, I’ll stick to the “UPC” barcodes used at stores: Some of the numbers have some actual meaning like who is the manufacturer of the product, but most of them are pretty unique to the product. This means that every product has its own unique code, and you can build a database to track what each of those products is and how many of them you have on hand. E.g.,
|Barcode|Name|Price|Qty. In Stock|
|:-:|:–|–:|–:|
|482674972492|Spumco Baked Beans, 355mL|$0.99|24|
|673987147214|Pants On Fire Frozen Boneless Chicken Wings, 2lb|$3.99|8|
|337592657321|Deez Beer Nuts, 600g|$2.99|20|
Latest Answers