The following file types can be found (not all in all folders)
.deb = Debian/Ubuntu Linux package (Install in a terminal via: sudo dpkg -i XXX.deb)
.dmg.gz = Apple Mac package (Mount the DMG and pull it into your Applications folder)
.rpm = SuSE/RedHat Linux package (Install in a terminal via: sudo rpm -i XXX.rpm)
.exe = Windows Installer (Install via double-click and follow the on-screen instructions)
.OSX.zip = Apple Mac package. When opened it will unpack, and you find the HO.app. Move it to Applications.
.zip = platform independend version (no special installer included)