The architecture of macOS describes the layers of the operating system that is the culmination of Apple Inc.'s decade-long search and development process to replace the classic Mac OS. After the failures of their previous attempts; Pink, which started as an Apple project but evolved into a joint venture with IBM called Taligent, and Copland, which started in 1994 and was cancelled two years later, Apple began development of Mac OS X with the acquisition of NeXT's NeXTSTEP in 1997. Note that Mac OS X was renamed to OS X in 2012 and then again to macOS in 2016.