If you're releasing a CD or DVD on a site like CDBaby or Amazon they want to see a barcode, whether you're using cd duplication services or a replication service, they want one on every item . So why does something that goes on a can of peas, have to go on your CD or DVD?

A barcode is graphic that can be read by a scanner.

OK, first everything that is sold in a store is typically expected to have a barcode. Each title is meant to have a unique series of numbers. For CDs and most items like that its a unique 12 digit number using 0-9. A source master number is only 6 digits and every barcode you assign starts with those same 6 numbers and you determine the last six. Nowadays most people just assign a back six but previously the next to last digit told you what it was. For instance, a "2" meant a CD or DVD and a "4" meant a cassette.

In its original days, it was a complicated process to determine a barcode. Before barcode software did all the work, it was adding up the odd-place digits and doing something to that number and then the even-place digits and do something with that second number, then adding them together and then that told you what the last or "check" digit was. It was ludicrously arcane.

Software is much easier.

Secondly, there is an international not for profit group that is charged with issuing master barcode numbers.

To obtain a master barcode number you apply for your own barcode through the GS1 US, a nonprofit group that shepherds the standards for international commerce. You can find them with a google search . Getting a master barcode is an investment in your business. You're signing up to be a member of their group and in exchange they provide you with a master number for your products. They don't care if you're self-publishing or a multi-national company, the costs are the costs to membership.

There are other opportunities where you can work with another member's master barcode and in most circumstances it will only help you to go that route. If you're looking for help with getting a barcode at no additional cost on your CD or DVD publication, you can check out a cd dvd replication service at www.cdmaker.com.

And thirdly, despite being universal, there is no great barcode repository in the sky that knows what everything costs.

Now, a barcode primarily serves an inventory purpose. Amazon's database of products they sell on their website is different from Walmart's. The first time your product hits a distribution network someone will actually need to input the title, author, description, product details and price. Then whenever your product is scanned at a sales point , their computer pulls up the name and price and also updates the inventory when its sold. So there is no universal repository outside of that store or chain of stores . The barcode in and of itself doesn't have a special code that tells the price. Its in the system - namely the prices is a field in the record of that CD or DVD but its not in the numbers themselves.

You can usually work with a cd duplication service that will provide you with a barcode. Most charge for that but if you're lucky you'll find one that does not.