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RAR Archive File Format, Version 2

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Format Description Properties Explanation of format description terms

Identification and description Explanation of format description terms

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
Relationship to other formats
    Subtype of RAR_Family, RAR Archive File Format Family
    Has later version RAR3, RAR Archive File Format, Version 3

Local use Explanation of format description terms

LC experience or existing holdings See RAR_Family.
LC preference None

Sustainability factors Explanation of format description terms

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 Explanation of format description terms

Other
Bundling/compression See RAR_Family

File type signifiers and format identifiers Explanation of format description terms

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 Explanation of format description terms

General See RAR_Family.
History See RAR_Family.

Format specifications Explanation of format description terms


Useful references

URLs


Last Updated: 07/11/2017