Comparison of archive formats

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There are many popular archive formats used to create archive files. The tables below compare many popular archive formats.

NOTE: This article appears to be in duplication/competition with List of archive formats.

Contents 1 Table Columns 1.1 Purpose 1.2 Filename Extension 1.3 Integrity Check 1.4 Recovery Record 1.5 Encryption 2 Table of Comparison 2.1 Notes 3 See also

[edit] Table Columns

The table columns contain the following general information:

[edit] Purpose

The earliest use of archive formats was for backup, mobility, and archiving. Improved versions of archive formats added the ability to compress the data to consume less storage space and network bandwidth. There are multiple compression algorithms available to statistically compress data. Some kinds of data can be highly compressed and some kinds of data do not benefit from compression. Currently, archive formats are also used to package software files for distribution, installation, and execution.

[edit] Filename Extension

The DOS and Windows operating systems required filenames to include a three-character extension to identify the file type and use. Filename extensions were (and are) required to be unique for each type of file. Many operating systems can identify a file's type from its contents without the need for an extension in its name. However, the use of three-character extensions has been embraced as a useful shorthand for identifying file types.

[edit] Integrity Check

Archive files are often stored on magnetic media, which is subject to data storage errors. Early tape media had a higher rate of errors than is expected for magnetic media today. Many archive formats contain extra data embedded in the files in order to detect data storage or transmission errors, and the software used to read the archive files contain logic to detect errors.

[edit] Recovery Record

Many archive formats contain redundant data embedded in the files in order to detect data storage or transmission errors, and the software used to read the archive files contain logic to detect and correct errors.

[edit] Encryption

In order to protect the data being stored or transferred from being read if intercepted, many archive formats include the capability to encrypt the data. There are multiple mathematical algorithms available to encrypt data.

[edit] Table of Comparison

The following table compares archive formats used for computer backups or transferring files.

Format	Filename extension	Created by	Introduced in	Based on	Purpose	Integrity check	Recovery record	Encryption supported	Unicode filenames	Modification date resolution
Archiving only
Archive (ar)	.a	CSRG	?	Original	Archive	No	No	No	No	?
cpio	.cpio	Bell Labs	Unix System V (1983)	?	Archive	Partial, select formats only	No	No	No	?
Shell Archive (shar and makeself)	.shar, .run	?	4.4BSD (1994)	Original	Archive	Yes, commonly MD5	Partial	Partial	Partial	?
Tape Archive (tar)	.tar	Bell Labs	Version 6 Unix (1975)	?	Archive	Partial, metadata only, by itself, but yes if used (as usual) with gzip	No	No	Optional1	?
Archiving and Compression
7z	.7z	Igor Pavlov	2000	LZMA	Compressed archive	Yes	No	Yes, AES	Yes	1 ms (maybe better?)
ACE	.ace	Marcel Lemke	?	?	Compressed archive	Yes	Yes	Yes, Blowfish	Yes	?
ARC	.arc	?	1985	?	Compressed archive	?	?	?	No	?
ARJ	.arj	Robert Jung	1991	AR001 and AR002	Compressed archive	Yes	Yes	Yes	No	?
Cabinet	.cab	Microsoft Corp.	Windows 3.1 (1992)	?	Compressed archive	?	?	?	?	?
Compact Pro	.cpt	Bill Goodman	May 5, 1990 (as "Compactor")	Original	Compressed archive	Yes	No	Yes	?	?
Disk Archive (DAR)	.dar	Denis Corbin	2002	tar	Compressed archive	Yes	Yes2	Yes	Yes	?
DGCA	.dgc	Shin-ichi Tsuruta	2001	GCA	Compressed archive	?	?	?	?	?
Format	Filename extension	Created by	Introduced in	Based on	Purpose	Integrity check	Recovery record	Encryption supported	Unicode filenames	Modification Date Resolution
LHA (also LZH)	.lzh, .lha	Haruyasu Yoshizaki	1988	Frozen	Compressed archive	Only on recent LHA releases	?	No	No	?
LZX	.lzx	Jonathan Forbes and Tomi Poutanen	1995	LZ77	Compressed archive	Only on recent LZX releases	?	?	?	?
Macintosh Disk Image	.dmg	Apple Computer	Macintosh System 7 (1991)	Original	Compressed archive	Yes	?	Yes	?	?
Partition Image (PartImage)	?	François Dupoux and Franck Ladurelle	2000	?	Compressed archive	?	?	?	?	?
PAQ (Several formats)	?	Matt Mahoney	2002–2006	Original	Compressed archive	?	?	?	?	?
Quadruple D	.qda	Taku Hayase (aka sandman)	1997	?	Compressed archive	?	?	?	?	?
RAR	.rar	Eugene Roshal	1993	Original	Compressed archive	Yes	Yes	Yes, AES	Yes	?
RK	.rk	M Software, Ltd.	?	?	Compressed archive	?	?	?	Yes	?
StuffIt (also SIT)	.sit	Raymond Lau	1987	?	Compressed archive	?	?	Yes	?	?
StuffIt X (also SITx)	.sitx	Aladdin/Allume Systems	2002	?	Compressed archive	?	Optional	Yes, RC4,Blowfish,AES,DES	Yes	?
ZIP (also PKZIP)	.zip	Phil Katz	1989	DEFLATE	Compressed archive	Yes	?	Yes, AES	No	1 s
Format	Filename extension	Created by	Introduced in	Based on	Purpose	Integrity check	Recovery record	Encryption supported	Unicode filenames	Modification Date Resolution
Software Packaging and Distribution
Debian package (deb)	.deb	Debian GNU/Linux	Debian 0.91 (1994)	ar, tar, and gzip	Software package	Yes	No	No	?	?
Macintosh Installer	.pkg, .mpkg (multi-package)	NeXT	NeXTSTEP 1.0 (1989)	?	Software package	Yes	?	?	?	?
RPM Package Manager (RPM)	.rpm	Red Hat Linux	Red Hat Linux 1.0 (1995)	cpio and gzip	Software package	Yes	?	?	?	?
Slackware Package	.tgz	Patrick Volkerding	Slackware 1.0 (1993)	tar and gzip	Software package	Yes	No	No	?	?
Windows Installer (also MSI)	.msi	Microsoft Corp.	Windows 2000 (2000)	?	Software package	?	?	?	?	?
Java Archive (JAR)	.jar	Sun Microsystems	JDK 1.1 (1997)	PKZIP	Software package	Yes	?	?	?	?

[edit] Notes

Note 1: While the original tar format uses the ASCII character encoding, current implementations use the UTF-8 (Unicode) encoding, which is backwards compatible with ASCII.
Note 2: Supports the external Parchive program (par2).

[edit] See also

• List of archive formats
• Comparison of file archivers
• Comparison of file systems
• List of file systems

v • d • e Archive formats (comparison by type) Archiving only ar · cpio · shar · tar · LBR Compression only bzip2 · gzip · LZMA · lzop · rzip · SQ · compress · LZW Archiving and compression 7z · ACE · ARC · ALZip · ARJ · Cabinet · cpt · DAR · dd · DGCA · .dmg · GCA · kgb · LHA · LZX · PAQ · RAR · qda · sit · SQX · zoo · ZIP Software packaging and distribution deb · pkg · RPM · MSI · JAR (WAR · RAR (Java) · EAR)