No it isn't, it is basically Amiga OS 3.x on an x86 processor and Today a bit more, it is a different Operating System, the real classic Amiga OS were running on Motorola, m68k and later on PPC boards, Amiga OS requires a special board with custom chips, such as AGA or ECS, OCS for graphics, even though it can be equipped with a graphics card, such as Voodoo and etc. But AROS is almost the same OS which is able to run on x86 architecture, as I know it is still developed, I tried it, it really looked cool, but it lacks lots of very good software if you want to move to it as the main OS.. you can find much more on
http://aros.sourceforge.net
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