On the other hand, some Apple press materials appear to indicate that this version is, in fact, the "Single Use" license: However, even if the retail edition of Snow Leopard is in fact a "Leopard Upgrade", the company has acknowledged that there is no technical barrier in that edition preventing a direct upgrade from Mac OS X "Tiger".and the installation discs provided through this program are clearly marked as upgrades unlike either of the retail editions.On those machines, Snow Leopard supports up to 16 terabytes of RAM.Newer Xserve and Mac Pro machines will run a 64-bit kernel by default; newer i Mac and Mac Book Pro machines can run a 64-bit kernel, but will not do so by default. Boot.plist will also enable users with compatible computers to permanently boot into 64-bit for those wishing to do so.Snow Leopard includes the following changes: While the Finder was completely rewritten in Cocoa, it did not receive a major user interface overhaul.
Snow Leopard was succeeded by Mac OS X Lion (version 10.7) on July 20, 2011.
They will run in 32-bit mode on machines with 32-bit processors, and in 64-bit mode on machines with 64-bit processors.
In addition, the Mac OS X kernel has been rebuilt to run in 64-bit mode on some machines.
Addition of new end-user features was not a primary consideration: its name signified its goal to be a refinement of the previous OS X version, Leopard.
Much of the software in Mac OS X was extensively rewritten for this release in order to take advantage fully of modern Macintosh hardware.