MenuetOS is an operating system with a monolithic preemptive, real-time kernel, including video drivers, all written in FASM assembly language, for 64-bit and 32-bit x86 architecture computers, by Ville M. Turjanmaa. It has a graphical desktop, games, and networking abilities ( TCP/IP stack), yet it still fits on one floppy disk. On an Intel Pentium MMX it can boot in .
MenuetOS was originally written for 32-bit x86 architectures and released under the GPL, thus many of its applications are distributed under the GPL.
The 64-bit MenuetOS, often referred to as Menuet 64, remains a platform for learning 64-bit assembly language programming. The 64-bit Menuet is distributed without charge for personal and educational use only, but without the source code.
Multi-core support was added on 24 Feb 2010.