Zip is a compression and file packaging utility for Unix,
VMS, MSDOS, OS/2, Windows 95/98/NT, Minix, Atari and Macintosh.

There are various software packages. They vary in cost from free
utilites to full blown commercial packages.

Each package has directions on unzipping a zip file. Below are
links to several of the sites for these packages:

Windows 95/98/NT:
WinZip - Full commercial package with Windows interface.
PKware - look for pkunzip.exe which is a free DOS unzip utility.
pkunzip.exe at UGA, free for download and use with DOS or in a DOS window.

Macintosh:
ZipIt - Commercial package.
Info-Mac Archive - look in the Compress... subdirectory for utilities.
Mac utilities - at UGA

DOS
PKware - look for pkunzip.exe which is a free DOS unzip utility.
pkunzip.exe at UGA, free for download and use with DOS or in a DOS window.

Unix:
At the command line type unzip and if you see instruction on how to use this command follow the instructions. If you get an error such as "command not found" talk to your system adminstrator about the availability of this utility.