AmigaOS is the OS which comes with an Amiga. AmigaOS has always been pre-emptively multitasking and features include “Datatypes” (filters enabling programs to read a new file format without being aware of it) and universal scripting support via ARexx. The OS hasn’t ever had memory protection, a fault which the current developers are slowly beginning to address.
AmigaOS 3.9 and below run on the “Classic” Amiga’s 68k processor, even if a PowerPC accelerator is installed. AmigaOS 4, the latest version (currently available as a developer pre-release) is PowerPC native and runs on the AmigaOne motherboards, as well as PowerPC accelerated A1200s and A4000s.
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