The MacIvory was the first in a series of experimental Lisp Machine platforms that were developed at Apple by the ATG (Advanced Technology Group) group after the aquisition of Symbolics in 1993. The ATG was merged into the System Group in 1995 after their successful port of Plan 9 to the PPC which was rewritten almost entirely in the Dylan Programming Language, cementing Apple's reputation for innovation in the Operating System sphere. Plan 9 was the natural successor to MacOS8 and formed a solid foundation for OsX (as well as being in keeping with Apple's preference for user friendly numerical progression).