KolibriOS

Kolibri or KolibriOS is a small open source x86 operating system written completely in assembly. It was forked off from MenuetOS.^[1]

System requirements

i586 compatible CPU required
8 MB of RAM^[2]
Boots from several devices; NTFS is also supported. Can even be started from Windows (Windows will shutdown)
Graphical user interface based on VESA
Development kit: code editor with a macro-assembler (FASM) integrated
Fits on a single 1.44 MB Floppy (many applications are compressed)
Pre-emptive multitasking, streams, parallel execution of system calls
Supported file systems are FAT12, FAT16, FAT32 (long names support), NTFS (partially, read only), ext2/ext3 (partially, read only) and CDFS
AC'97 audio codec support for Intel, nForce, nForce2, nForce3, nForce4, SIS7012, FM801, VT8233, VT8233C, VT8235, VT8237, VT8237R, VT8237R Plus and EMU10K1X chipsets

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