Mac OS On Amiga
Also introduced for the Amiga were two products, A-Max (both internal and external models) and the Emplant expansion card. Both allowed the Amiga to emulate an Apple Macintosh and run the Macintosh Operating System. It required an Apple Macintosh ROM image, or actual ROMs in the case of A-Max, which needed to be obtained from a real Macintosh. The user needed to own the real Macintosh or Mac ROMs to legally run the emulator.
In 1988 the first Apple Mac emulator, A-Max, was released as an external device for any Amiga. It needed Mac ROMs to function, and could read Mac disks when used with a Mac floppy drive (Amiga floppy drives are unable to read Mac disks. Unlike Amiga disks Mac floppy disks spin at variable speeds, much like CD-ROM drives). It wasn't a particularly elegant solution, but it did provide an affordable and usable Mac experience.
ReadySoft, makers of A-Max, followed up with A-Max II in the early 1990s. A-Max II was contained on a Zorro-compatible card and allowed the user, again using actual Mac ROMs, to emulate a color Macintosh. In fact, an Amiga 3000 emulating a Mac via A-Max II was significantly faster than the first consumer color Mac, the LC.
Over time full-software virtualization was available, but a ROM image was still necessary. Example virtualization software include ShapeShifter (not to be confused with the third party preference pane ShapeShifter), later superseded by Basilisk II (both by the same programmer who conceived SheepShaver, Christian Bauer), Fusion and iFusion (the latter ran classic Mac OS by using a PowerPC "coprocessor" accelerator card).
Virtual machines provide equal or faster speed than a Macintosh with the same processor, especially with respect to the m68k series due to real Macs running in MMU trap mode, hampering performance. Also, immediately after 68k Macs were discontinued, there was a lack of native PowerPC Mac software: Amiga computers with 68060 CPUs running ShapeShifter or Fusion were able to run 68k Macintosh code faster than real Macs.
One should note that although Amigas were very successful at emulating Macintoshes, it was never considered to be a Macintosh clone as it could not use Mac OS as a primary operating system.
Modern Amigas like AmigaONE and Pegasos can emulate Macintosh Machines by using Basilisk II or Mac-on-Linux.
Read more about this topic: Emulation On The Amiga