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UUTool

Freeware application

Wikipedia contributorsAdapted for Fathomly · View authors
1 min read
Source updated July 18, 2026

UUTool was a freeware application written for the Apple Macintosh by Bernie Wieser. The purpose of UUTool was to uuencode and uudecode files, however, the application functionality grew to translate uLaw encoded files to AIFF format, segment large uuencoded files, and recombine multiple uuencoded files for decode.

01Technical details

UUTool uuencoded files and attached the .uu extension. However, UUTool was the first Macintosh program that encoded the data fork, resource fork, and finder information into one uuencoded file with the .mu extension. The format for this was to catenate the three pieces of file information and uniquely name the resource fork and finder info as files. This allowed for some interoperability on non-Macintosh platforms.

Example

begin 0700 myfile ... end begin 0700 .rsrc ... end begin 0700 .finfo ... end

02Version history

1990 v1.0 first 68k version
1994 v2.3.2 most pervasive version and last of the 68k line
1995 v2.4 first (and last) FAT version for PPC
Watch videos about UUToolExplainers and documentaries on YouTube (opens in a new tab)

Sources and credits

This article is adapted from the Wikipedia article “UUTool”, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.

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