RAR Archive File Format, Version 2

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RAR Archive File Format, Version 2

Table of Contents

Identification and description
Local use
Sustainability factors
Quality and functionality factors
File type signifiers
Notes
Format specifications
Useful references

Format Description Properties

ID: fdd000457
Short name: RAR2
Content categories: aggregate
Format Category: file-format
Other facets: container-bundle, compression
Last significant FDD update: 2017-03-28
Draft status: Preliminary

Identification and description

Relationship to other formats
Full name	RAR Archive File Format, Version 2
Description	Roshal ARchive format version 2 (RAR2) is said to be built off RAR1.5 but there is no publicly available information for RAR1.5 to compare it to. Comments welcome. Structurally, RAR2 is comprised of a marker block, archive header, file header(s) and recovery information. These can be augmented as needed with optional comment headers, extra information blocks and subblocks. See RAR_Family for additional details on the file structure. RAR2 is compatible with WinRAR 2.0 and Rar for MS-DOS 2.0. The now-defunct unrarLib tool only works with RAR files up to version 2. RAR2 added functionality for multimedia compression for true color bitmap images and uncompressed audio and introduced the archives data recovery protection record. Maximum compression dictionary size is increased up to 1 MB. Later versions increased this dramatically with RAR5 bringing the size up to 1 GB.
Production phase	See RAR_Family
Subtype of	RAR_Family, RAR Archive File Format Family
Has later version	RAR3, RAR Archive File Format, Version 3

Local use

LC experience or existing holdings	See RAR_Family.
LC preference	None

Sustainability factors

Disclosure	See RAR_Family
Documentation	See RAR_Family
Adoption	See RAR_Family
Licensing and patents	See RAR_Family
Transparency	See RAR_Family
Self-documentation	See RAR_Family
External dependencies	See RAR_Family
Technical protection considerations	See RAR_Family

Quality and functionality factors

Other
Bundling/compression	See RAR_Family

File type signifiers and format identifiers

Tag	Value	Note
Filename extension	See note.	See RAR_Family
Internet Media Type	See note.	See RAR_Family
File signature	Hex: 52 61 72 21 1A 07 00 ASCII: Rar!	Wikipedia states that this magic number is applicable for RAR1.5 - RAR4 although Gary Kessler's File Signature Table and RAR 5.0 archive format tech note only specifically list this magic number for RAR4, not earlier versions. Acritum Software's description of RAR version 3.93 (not described at this site) lists this value for all versions since RAR1.5.
Pronom PUID	x-fmt/264	See http://www.nationalarchives.gov.uk/PRONOM/x-fmt/264 for RAR2
Wikidata Title ID	See note.	See RAR_Family.

Notes

General	See RAR_Family.
History	See RAR_Family.

Format specifications

RAR version 2.02 - Technical information (http://libxad.cvs.sourceforge.net/viewvc/libxad/support/formats/RAR202.txt).
See RAR_Family

Useful references

URLs

See RAR_Family
PRONOM entry for x-fmt/264 (http://www.nationalarchives.gov.uk/pronom/x-fmt/264). Information in PRONOM from UK National Archives about RAR2. PUID: x-fmt/264.

Last Updated: 12/27/2022