Originally the PC came with a flakey 360KB floppy disk and then the PC AT delivered a higher capacity 1.2MB the storage for removable files was not a major problem. DOS programs tend to be quite small.

Over time however programs became more complex and more and more large text documents began to pressure storage.

In the early days some CP/M programs were ported to the PC. These early programs were clumsy and the new ARC program was able to do the work of several CP/M programs.

Around 1986 PKXARC was released that could extract ARC files much faster than the original ARC program make it very popular. When PXARC was release however a legal fight ensured that eventually leg to change.

Litigation was messy and Phil Katz lost a bundle.Eventually PKPAK and PKUNPAK were released. These were replaced quickly with PKZIP which became widely used. Details were published to expand and decompress ZIP files making it very popular.

Converting large numbers of files from one archive format to another made hard disk workloads higher than most realized. Hard disks in the 1980s were far from universal and and larger capacity disks are very expensive.


The file format of the files created by these programs, which file format is original with the first release of this software, is hereby dedicated to the public domain. Further, the filename extension of “.ZIP”, first used in connection with data compression software on the first release of this software, is also hereby dedicated to the public domain, with the fervent and sincere hope that it will not be attempted to be appropriated by anyone else for their exclusive use, but rather that it will be used to refer to data compression and librarying software in general, of a class or type which creates files having a format generally compatible with this software.


Microsoft eventually licensed the ZIP format Phil Katz and it has been part of Windows ever since.  Zip files are treated like folders albeit with some lag to compress or expand files.


Phil Katz (November 3, 1962 – April 14, 2000)  was found in a hotel room, dead, still clutching an empty peppermint schnapps bottle. Katz died from pancreatic bleeding. Katz had struggled with alcoholism since he was a teen.