US Patent 7536684 Software documentation generation using differential upgrade documentation

A software application includes a document generator. A user can download from an upgrade website documentation (e.g., release notes) describing the differences in operation between a post-upgrade version of the application that would result if a target upgrade is implemented and a pre-upgrade version of the application, e.g., the one available on the user computer system. The document generator can generate full documentation for the post-upgrade version from the pre-upgrade documentation and the upgrade documentation. The post-upgrade documentation has a revision display mode and a non-revision display mode, the former showing the changes from the operation of the pre-upgrade version to the operation of the post-upgrade version.