--Elen

Answer: If you're talking about a ZIP format file, they're all over the place. I suspect though that you're looking for a utility calledPKZIP or Winzip to either create or uncompress a ZIP file.

More on those utilities below, but first a little background on ZIP files.

PKWARE Inc. of Brown Deer, Wisconsin, unveiled the ZIP file format in 1989. The format was created so that data could be compressed smaller for storage. In those days data storage hardware was very expensive. The invention was received with open arms, especially by computer users who liked to trade files between computers via snail-slow modems.

ZIP files are created by crunching large data files with a data "trash compactor." The compactor can also work in reverse. It can uncrunch a ZIP file back to the way it looked before. Not so in an auto wrecking yard.

In some cases, a file can start out as 500K in size and be reduced to a 50K ZIP file. A ZIP utility achieves this by looking for patterns in the file and replacing them with markers.

"Basically it takes out all redundant information like blank space and looks for repetition in the binary code," said Bob Gorman, PKWARE's marketing manager.

Think of a long line of thousands of Cyberwalker clones (no sheep jokes, please), all standing shoulder to shoulder, each wearing either a red or blue shirt. There could be hundreds of instances where you'll spot a red Cyberwalker on either side of a blue Cyberwalker. If you pulled these three out of the line and replaced them with a sign that said "RBR" and did that repeatedly every time you saw a pattern like that, the line would get shorter.

This was useful technology when hard drives were expensive, because you could put more data into less space, if you were storing it. On the Internet, this is still useful, because a ZIPped file can be downloaded faster than an uncompressed file.

Another feature of a ZIP file is you can take several files, compress them smaller and then pile them all into one ZIP file. It's handy when you want to move a whole directory of files onto a floppy disk.

PKWARE makes a series of file compression utilities for different operating systems.

PKZIP 2.6 for Windows is the kind of utility Elen is probably looking for. There's also a version for the Mac and other platforms.

A trial version can be downloaded at www.pkware.com. The full program, which also supports a variety of other file compression formats, costs $49 US and can also be downloaded using the company's secure credit card transaction page. Or call 414-354-8699.

There is also a utility called WinZip by Nico Mak Computing available at www.winzip.com. The full version of WinZip 6.3 for Windows 95, 98 and NT costs $29 US. A trial version is also available. Or call 1-713-524-6394.

Finally, consider looking at NetZip and utility that's lets you unzip items as they arrive. Quite a clever program. Click here for more info.