When you compress a file or folder in the Finder via the Create Archive command, a ZIP file is created using the current date as modification date. But when you’re archiving older data, it’s much more useful for the ZIP file date to reflect the date of its contents, since a few years from now [...]
Content Strategy Forum London

CHM Viewers for Mac OS
A quick search for Mac CHM viewers yields a handful of open source & shareware apps which provide Mac users access to Windows help files in the Compiled HTML Help (CHM) format. A few older shareware apps such as Chimp and CHM Viewer are only available in PowerPC versions and apparently no longer actively developed. [...]