JavaOS is not a modern operating system: it has no kernel, no virtual memory, and no disk file system. On the other hand, it is aimed at the future: it is designed for a networked world; it removes almost all the hassles of owning and maintaining a personal computer; and it has a graphical user interface, but no command line interpreter.
It is almost entirely written in Java, and it's small and fast.
Dr. Mitchell has a Ph.D. from Carnegie-Mellon University and a B.S. from the University of Waterloo, Canada. He has worked on compilers, interactive programming systems, programming language design, document preparation systems, user interface design, graphics hardware, distributed transactional file systems, and distributed, object-oriented operating systems.