October 14, 20259
RISC Operating System
Originally Acorn Computers, now maintained by RISC OS Open Ltd
riscos
October 14, 202512
GE Operating System
Advanced user account controls, file permissions, job accounting.
geos
October 14, 202512
Serenity Operating System
SerenityOS Community-led project (founded by Andreas Kling)
serenityos
October 14, 202515
Haiku Operating System
Haiku is a unique project that preserves the innovative spirit of BeOS—focusing on a fast, elegant, and unified personal computing experience
haikuos
October 14, 202513
Windows Operating System
Windows OS, developed by Microsoft in 1985, is the world’s most widely used desktop operating system.
windowsos
October 14, 20259
FreeRT Operating System
FreeRTOS Real-time microkernel (non-monolithic
FreeRTOS