The standard linear barcodes simply identifies an object by associating a number to it. The rest (where the information is processed and stored) is held in a computer system in the form of a database. Once the object has been scanned (using a barcode reader), the system pulls up the pertinent information for that object.
An example of this is your grocery store, or supermarket, or Wal-Mart, etc. at the checkout counters.
This number is 12 or 13 digits in length and stored within 14 digits in length with leading zeroes.
There are also omnidirectional DataBars that allow for additional info, such as sell-by date, weight, and lot number.
But these are intended to be hand scanned and cannot be used with standard onmidirectional readers.