From Logiciels & Services Duhem:
MacDisk is an utility to read/write/format Macintosh media on a PC without any add-on. MacDisk manages floppies, CD-ROMs, Zips, Jaz, all removable media and even plain hard disks. MacDisk is a must if you have to use data file produced on the Macintosh or to deliver data files to Macintosh users. MacDisk manages the Macintosh signatures and adds a corresponding extension to the files copied from the Mac to the PC. Conversely, MacDisk gives a signature to the files copied on the Macintosh volume to make 'double-clickable' icons."