Place the entire barcode directory into the directory in which you've chosen to place contrib modules (usually sites/all/modules).
Enable the barcode module by navigating to: administer > modules
Copy your font to the barcode/ folder (D6)
Finish the configuration at admin/content/barcode (admin/settings/barcode in D6 v2 and admin/config/media/barcode in D7 v2) specifying the location of your font file and the desired encoding.
Add barcode fields to your content types as desired.
Features:
Generate a barcode image on the fly. It supports QR Code, EAN-13, EAN-8, UPC-A, UPC-E, ISBN, 2 of 5 Symbologies (Strandard, Industrial, Interleaved), Postnet, Codabar, Code128, Code39 and Code93 symbologies.
You can also display the barcode as simple text, or an image.
You can provide your own font file at fonts directory
The Book Copy module allows users to copy complete books or subtrees of books.
When books are copied the user initiating the copy will be the node author of all book sub-pages. This will allow the user to adjust content to their purpose while keeping the initial content unedited.
This module requires that Replicate module be installed and enabled. It provides an elegant API for cloning items successfully and the 6.x book_copy api has been dropped in favor of this one.
Integrations / support
Drush - Copy books via the command line with Drush. Outline Designer - duplicate parts of book outlines using the outline designer UI, powered by Book Copy. Book Delete - accounts for Book Delete module if it is installed so the two can coexist.