Apple buried Copland 30 years ago. Now the failed OS boots in a browser

Thirty years after Apple abandoned Copland, its doomed attempt to create a modern Mac operating system, a new emulator lets you try the final developer build in your browser. Copland was intended to replace Apple's System 7 with a PowerPC-native operating system built around a microkernel, protected memory, and preemptive multitasking for system services. Three unfinished developer builds – D7E1, D9, and D11E4 – are publicly known.