- BarCode 1
- Categorised lists of barcode related links, references, and specifications. Includes a search facility and an FAQ.
- Barcode Contents
- Google's Zxing project guide to the standard encoding of information in 2D barcodes.
- Barcode Island
- Provides general and technical information on numeric, alphanumeric, and 2-dimensional barcodes. Includes a discussion forum.
- UPC Database
- Search or download a database of manufacturers by manufacturer code, and a file of items by UPC.
- Wikipedia: Barcode
- Encyclopedia article including the history, use, symbology, and benifits of barcodes.