Mac OS X Server 1.x

Mac OS X Server 1 is the first operating system by Apple that is based on NeXT technology. It is the commercial release of the Rhapsody project, which was met by negative reactions by software vendors regarding its intention to run all existing classic Mac OS code in a virtual machine, requiring complete rewrite of applications in order to run natively.

History
This project was announced in January 1997 at MacWorld Expo and was demonstrated at the 1997 Worldwide Developers Conference (WWDC).