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Name Hierarchical File System Plus
Other names HFS+, Mac OS Extended, HFS Extended
Identifiers PUID:  fmt/1742
Classification Aggregate
Description Hierarchical File System Plus (also known as HFS+, Mac OS Extended or HFS Extended) is a file system developed by Apple Inc. as a successor to the Hierarchical File System (HFS) [fmt/1105]. The system was introduced in January 1998 with the release of Mac OS 8.1 and continued to be the primary file system on Apple operating systems starting with Mac OS X, as well as one of the primary file systems used by the iPod portable media player. It features improvements to HFS, such as a 32-bit file length field rather than 16-bit to allow for much longer files names and adds support for Unicode characters in file names up to 255 characters long, containing any characters in the Unicode repertoire (though there may be OS or API-specific restrictions on permittable characters). Journaling was added in 2003 and case-sensitive file names were introduced under the HFSX option. It was replaced with the Apple File System (APFS) released with macOS High Sierra in 2017.
Byte order  
Related file formats None.
Technical Environment  
Supported until  
Format Risk  
Developed by None.
Supported by None.
Source The Church of Jesus Christ of Latter-Day Saints / The Church of Jesus Christ of Latter-Day Saints
Source date 17 Aug 2022
Source description  
Last updated 17 Aug 2022
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