How does a barcode work?

This is an example of a Code 128 barcode that contains letters. 

code 128 barcode

When the barcode scanner reads the bar code, it translates the bars into numbers or letters.  It then sends that information into the computer, or terminal or whatever device it is attached to.  In the case of a supermarket it would send the numbers to the central computer in the back office, and ask the computer to send back the price and description information that corresponds to the UPC number.    There is no price in the UPC number. The price and description, weight, etc are stored somewhere else.

If you have a product that you intend to sell through retail or distribution channels, you will need a unique barcode for that product.  Click here for information on How to get a barcode.

If you would like to create your own barcode, we have free utility on our website to do that.  Click here to Create your own barcode.

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Other articles that may interest you:

How to get a Bar Code

History of the Bar Code

YouTube Video's that illustrate how to make labels and bar codes:

1. Create a QR Code for business cards

2. QR Code for Signs and Flyers

3. Create a UPC Bar code

4. Make sheets of bar code labels

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Craig Aberle
+3 #3 Craig Aberle 2011-08-01 16:51
Yes. You can create your own bar codes with built in expiration dates.
For example, rather than just create a code “123456” you could make a bar code like this “123456,08/31/11”
You just have to be able to read the code and decipher it.
Does that help?
Click on the MAKE A BARCODE link on the left to experiment.
+1 #2 steven 2011-08-01 16:41
pleas make it at least in a month or so cuz by then my team will have chosen another topic
+1 #1 steven 2011-08-01 16:36
could you add something to the barcode that would tell a com something like the expiration in a lego league group, we build robots out of legos and put them in competition,but we also have to reaserch on a specific theam. this years theme is prevent food contamination please get back to me