muLinux is an Italian, English-language lightweight Linux distribution maintained by mathematics and physics professor Michele Andreoli, meant to allow very old and obsolete computers (80386, 80486 and Pentium Pro hardware dating from 1986 through 1998) to be used as basic intranet/Internet servers or text-based workstations with a UNIX-like operating system.

It was also designed for quickly turning any 80386 or later computer into a temporary, powerful Linux machine, along with system repair, education, forensic analysis and what the developer called proselytizing.

In 2004 reviewer Paul Zimmer wrote, "Although there are several other single-floppy Linux distributions, none can match muLinux's extensive and unique combination of useful features.

"[3] muLinux could also be unpacked and installed by a self-executable archive, or extracted directly, onto an old DOS or Windows 9x (umsdos) partition without harming the current OS.

Since the distribution was always wholly targeted at old hardware and meant to have a tiny footprint, Andreoli warned at the time that muLinux should not be used to evaluate Linux or open source software.