What are the advantages and disadvantages of bar codes?

There are two basic advantages to barcode over manual data entry: Speed, and Accuracy. For 12 characters of data, keyboard entry takes 6 seconds. Scanning a 12 character barcode takes .3 seconds. The error rate for typing is one substitution error in every 300 characters types. Error rated for barcode range from 1 substitution error in every 15,000 to 36 trillion characters scanned (depending on the type of barcode). A data entry error will translate into additional costs for a business which ranges from the cost of rekeying the data to shipping the wrong product to the wrong customer. Saving from these two advantages will usually pay for the cost of a barcode system in under two years. The only disadvantage is that data must be coded in the barcode. This can be an additional cost, however the key to an effective barcode system is to generate the barcode as close to the source of the data as possible. That means that the source of a product should be bar coding data that others in the supply chain will use.
speed and accuracy are advantages and the disadvantage is that w/out a description on the barcode you need a scanner or a computer to tell you what the product is