<operating system> Apple Computer, Inc.'s next-generation operating system for PowerPC processor-based systems capable of running Mac OS. Rhapsody includes four components: the Core OS, the Blue Box (the implementation of the Mac OS within Rhapsody), the Yellow Box, and the Advanced Mac Look and Feel.
"Rhapsody for Intel" runs on Intel processors [which ones?]. It includes the Core OS, the Yellow Box, and the Advanced Mac Look and Feel, but lacks the Blue Box and therefore is unable to run Mac OS software.
"Rhapsody Developer Release" is a developer-only release of Rhapsody, scheduled for release in late 1997. It will go to all members of the Macintosh Developer Program and the Apple Media Program worldwide who have signed nondisclosure agreements.
"Rhapsody Premier Release" will be the second release of Rhapsody, scheduled for early 1998. It is meant for early adopters and will include a partially finished human interface and a partial implementation of the Blue Box.
"Rhapsody Unified Release" will be the third release, scheduled for mid-1998. It will be the first public release, and it will include the first full implementation of the Rhapsody human interface and the Blue Box.