This symbology was originally designed to be easily scanned even when printed on dot-matrix printers or on multi-ply paper such as receipts, invioces and alike. Codabar is being replaced by newer symbol sets that store more data in a smaller area but there is already a large install base where these codes are currently being used.
Codabar uses 4 bars and 3 spaces to encode each character. A narrow space is used between characters. The characters that can be encoded using codabar are the digits 0-9 and the characters $ (dollar sign) - (dash) + (plus) : (colon) / (slash) . (period). There are also 4 start/stop characters represented by A, B, C, D or possibly T, N, * (asterisk), E. These start and stop characters are not represented as data just like other barcodes.
Using the 16 different variations of start and stop characters make it possible to identify some applications of the barcode. For example FedEx tracking numbers start with C and end with D while library barcodes start with A and end with B. This doesn't always hold true because there are so many applications of these numbers but this can be a guide to help identify how the barcode is being used.
If you want to make your own Codabar barcode, please visit our barcode generator page. Save the images you create and use them how ever you like.