Acronym for Hierarchical File System, which is the native filesystem used on most Apple computers.
MacOSX uses HFS+, which is the next version of HFS. HFS+ supports journalling.
See also: http://markhobley.yi.org/mdirs/index.html Modified Directory Structure
CategoryFileSystem
CategoryJournallingFileSystem
CategoryOtherFileSystem
One page links to HFS:
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