Amazon.com description: Product Description: This book is written without any previous knowledge of the subject who over the years have asked the author what these bar codes are all about. It deals with why they were invented, who created them, how you can understand any number and bar code, and how they are managed and used. It is lightly written, entertaining, humorous and full of stories not previously recorded about their 40-year life. For users or students of bar codes, it will widen their knowledge and understanding. For others it will provide them with the enjoyment of becoming an instant expert on the subject.