MenuetOS
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 1.44 MB floppy disk. On a Intel Pentium MMX 200 MHz it can boot in 5 seconds.
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