Tanenbaum–Torvalds debate

In 1987, Tanenbaum wrote an clone of UNIX, called MINIX (MIni-uNIX), for the IBM PC. It was targeted at students and others who wanted to learn how an operating system worked. Consequently, he wrote a book that listed the source code in an appendix and described it in detail in the text. The source code itself was available on a set of floppy disks. Within three months, a USENET newsgroup, comp.os.minix had sprung up with over 40,000 readers discussing and improving the system. One of these readers was a Finnish student named Linus Torvalds who began adding new features to MINIX and tailoring it to his own needs. On October 5, 1991, Torvalds announced his own (POSIX like) kernel, called Linux, which originally used the MINIX file system but is not based on MINIX code.

Although MINIX and Linux have diverged, MINIX continues to be developed, now as a production system as well as an educational one. The focus is on building a highly modular, reliable, and secure, operating system. The system is based on a microkernel, with only 5000 lines of code running in kernel mode

The Tanenbaum–Torvalds debate is a debate between Andrew S. Tanenbaum and Linus Torvalds, regarding Linux and kernel architecture in general. Tanenbaum began the debate in 1992 on the Usenet discussion group comp.os.minix, arguing that microkernels are superior to monolithic kernels and therefore Linux was, even in 1992, obsolete. Other notablehackers such as David S. Miller and Theodore Ts'o joined the debate. This is the link to debate

http://groups.google.com/group/comp.os.minix/browse_thread/thread/c25870d7a41696d2/f447530d082cd95d?tvc=2&pli=1

by the way  Andrew S. Tanenbaum's FAQ is also an interesting read :P