A file with .zip extension is an archive that can hold one or more files or directories. The archive can have compression applied to reduce the ZIP file size. ZIP file format was made public in February 1989 by Phil Katz. It was part of the PKZIP utility, created by PKWARE, Inc.
The .ZIP file format specification is formally named “APPNOTE – .ZIP File Format Specification”. It is published on the PKWARE.com website since the late 1990s. Several versions of the specification were not published. Specifications of some features were published by PKWARE a few years after their creation.
Many compression utilities can convert ZIP files by extracting their contents and then compressing them in a different archive format. For example, PowerArchiver can extract the contents of a ZIP file, then compress them as various archive types.
ZIP archiving and compression is used by many people and programs. It merges an extensive structure into a single file, which facilitates sending and transferring of files.
It utilizes lossless data compression technology. The contents of these files are reduced in size with no loss in quality. This makes sharing large volumes of information much easier.
Each file in a ZIP archive is compressed individually, not as the whole archive. This allows the program to compress each element in the most appropriate way. The DEFLATE method is most commonly used for all 10 different types of files ZIP files can contain.
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