Zoo (file format)
data compression program and file format

zoo is a data compression program and format developed by Rahul Dhesi in the mid-1980s. The format is based on the LZSS compression algorithm and compressed files are identified by the .zoo file extension. It is no longer widely used. Program source code was originally published on the comp.sources.misc Usenet newsgroup, and was compatible with a variety of Unix-like operating systems. Binaries were also published for the MS-DOS and AmigaOS user communities.
zoo features
zoo archives can store multiple "generations" of a file; if files are added to an archive with the same pathname yet more recent date, if generations are enabled for the archive the older version(s) will be retained (with a semicolon and version number, similar to version numbers in the VMS and RT-11 operating systems) as the new file is added. This allows files that are frequently modified to be backed up in such a way as to allow access to previous versions (up to the version limit chosen) from one archive.
The public source identifies “Zoo (file format)” as data compression program and file format. This brief keeps that definition visible, then builds a research path around file, format and data.
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A short description can identify a subject without explaining its stakes. For “Zoo (file format)”, the useful work is to connect “data compression program and file format” to the records capable of establishing context and consequence.
The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Sep 13, 2026. The linked authority identifier is Q219983. None of the 0 selected statements returned an explicit reference.
Overview language is designed for orientation and should not be treated as a substitute for the evidence cited beneath it. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
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This entry incorporates text from “Zoo (file format)” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.