by Cobor

Created on: May 29, 2008

The creation of ZIP file format can be attributed to Phil Katz, founder of PKWARE.

We were in the mid-1980 when the SEA (System Enhancement Associates), a small company run by Thom Henderson, created a file storage in a format called ARC, and a program (also called it ARC) capable of compressing and decompressing files in this format.
The program which, together with its code, was issued with license shareware has ensured that this file format quickly become a de facto standard. Shortly after Phil Katz has issued PKXARC, a software package compatible with ARC, developed using the optimized assembly language and for this reason, however, was fastest of the implementation of SEA which was developed using the language C.

The SEA, which was not liked competition from Katz Katz cited in court for trademark and copyright, alleging that he had plagiarised sections of code. Katz lost the lawsuit and was forced to pay $ 62500 to SEA to compensate the damage and legal costs. During court proceedings was shown that Katz had used that for most of its programme source code of ARC, which had only carried out an optimization code for increasing speed. In the first place has changed the length of speech used by the algorithm by 12-bit to 13 bit with a compression higher for the typical binary files. Following the lawsuit, Katz changed the names of its programmes in PKPAK and PKUNPAK.

After this fact Katz has also created its compressed file format, now known worldwide as the ZIP format. The ZIP format is more resistant to data loss compared to the ARC format because of the catalogue is storage and is also flexible and open to a possible future expansion as it provides room for further compression algorithms.
Once issued the new format PKZIP many users have abandoned ARC because less fast and less compression in effigy; other reason for leaving ARC was unclear policy that SEA has done on property rights after the file format ARC was very used between users of the community online.

The ZIP format is an open format and Katz has released publicly on the technical documentation together with the first version of its PKZIP archiver, in January 1989.

It was Robert Mahoney, a friend of Katz, suggesting the name zip (meaning speed) wanting so mean that their product would have been faster than ARC and other compression formats.

In the mid 1990, as the implements computer operating systems and programs with graphical user interface many users have not found more at ease with the line of command functioning of PKZIP. Seeing an opportunity, some shareware authors have started to produce programs compression and storage with graphical user interface. Many of these have used the ZIP format. WinZip was among the most popular. Even PKWARE offered a graphic version of PKZIP. The use of these programs was easier to learn than the old command line.

At the end of 1990, several software file managers have started to integrate support for the ZIP format in their user interface, first of all Norton Commander and its clones. A support ZIP format was also added to Windows Explorer with the package Plus! for upgrading the Windows 98 and later included in Windows ME and Windows XP; ZIP format is also supported in the Finder of Mac OS. By 2002, all the major desktop environments already included support for ZIP files in their file manager: A ZIP file is usually presented as a directory or folder, so that the files are copied incoming and outgoing in the same way like any other folder and the compression is handled in a largely transparent to the user. This has eliminated the need to learn and use a specialized tool and interface for the archive file and compression.

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