.zip

Compressed files that may contain one or more files when uncompressed on a PC.

Windows XP can decompress .zip files without additional software by right-clicking on the .zip file and selecting the 'Extract All' option in the menu.

For older versions of Windows you will need a compression utility to decompress the files. A selection freeware, shareware and commercial utilities for the PC can be found on the Tucows web site.

.hqx

Compressed files for the Apple Mac and can be uncompressed by Mac OSX by double-clicking the downloaded files.

A selection freeware, shareware and commercial utilities for the Macintosh can be found on the Tucows web site.