UPC-A

UPC (Universal Product Code) is probably still the most commonly-encountered bar code in everyday life, though these days QR codes are catching up. Just about every product has one, and they are used at the checkout in most large stores to scan purchases into the cash register. UPCs were developed at IBM in the early 1970s and were in widespread use by the end of that decade. They are still in heavy use, though experts regard them as obsolete compared to newer bar code technologies which can encode larger amounts of information in a smaller size.