aros is source compatible. that means it is binary compatible when run on amiga (m68k). on x86 you wull need an emulator. afaik there is janus uae, but im no expert on aros x86. also unlike what minous says aros s not just compatible with 3.1 api. this is just a bottom line. in some areas it improves upon or is clearly superior, in some others it is still lacking. it lacks for instance a native reaction gui implementation. instead it has mui compatible zune.