This document discusses using progressive barcodes for archiving applications. Progressive barcodes encode data in both black-and-white and color channels, allowing two channels of information. They are suitable for archiving where one channel, like a document ID, remains static, while the color channel can dynamically track document changes. The document proposes an inference model where tags on individual archive items can be inferred from tags on containing folders and computers, reducing the number of required tags. Progressive barcodes combined with inference could track documents and versions without opening each container.