ZIP File

The data in a zip file can be compressed in a variety of compression methods:

• Store (no compression)
• Shrink
• Reduce (levels 1-4)
• Implode
• Deflate (the most commonly used compression method for zip files)
• Deflate64
• bzip2
• LZMA (EFS)
• WavPack
• PPMd
• PKWARE Data Compression Library (DCL) Implode (not documented)
• IBM TERSE (not documented)
• IBM LZ77 z Architecture (PFS) (not documented)

The deflate algorithm is also used for gzip (RFC 1952) and ZLIB (RFC 1950).

zip is a Unix/Linux tool to create zip files in a Linux/Unix shell

The PowerShell command noun archive has the two verbs compress-archive and expand-archive.

7-Zip is a free open source software to create archives. With its command line version 7z.exe, its possible to manage zip files on a Windows command line.

The Windows Resource Kit tool compress.exe.

The Perl modules Archive::Zip and IO::Compress::Zip allow to create Perl scripts that create zip solutions with some program-logic.

In the SAS system, there is the statement filename zip

The ZIP file specification does not specify a standard way of encoding filenames with non-ASCII characters.

Info-ZIP is an implementation of the zip file format that adds support for

• Unix file system features such as user and group id
• NTFS filesystem permissions

When extracting an info-zip file, that was created on Unix, on Windows, or vice versa, an attempt is made to translate NTFS permissions from/to Unix permissions. Apparently, this might lead to issues.

A zip file (and some other formats that are based on it) has as its first two bytes the letters PK (hex: 50 and 4B) followed by 0304, 0506 or 0708.

PK stands for the initials of the creator of the zip file format: Phil Katz.

The MIME type of a zip file is application/zip.

The .NET class System.IO.Compression.ZipFile with this PowerShell function that allows to selectively add files from a file system tree.

In a Windows console (cmd.exe or PowerShell), a zip file can be unzipped with tar.exe.

Python: shutil.unpack_archive is able to extract the content of a zip file (if it is not using compression type 9 (Deflate64/Enhanced Deflate)).

The built-in function zip has nothing to do with zip files!

SQLite has a archive mode that allows to create zip-like SQLite databases.

archive files

The vim plugin zipPlugin.vim

zipfldr.dll, zipcontainer.dll

There are quite a number of file types that are stored in zip files, such as .dacpac, .jar, .nupkg, .xpi and all Office files whose extensions match .*x (for example .docx) and *m (for example .xlsm).

The PowerShell module zip

The Oracle PL/SQL package zipper

APPNOTE.TXT: ZIP File Format Specification