The UNIX system has been in wide use for over 20 years, and has helped to define many areas of computing. Although numerous organizations have contributed (and still contribute) to the development of the UNIX system, this book will primarily concentrate on the BSD thread of development:
• Bell Laboratories, which invented UNIX
• The Computer Systems Research Group (CSRG) at the University of California at Berkeley, which gave UNIX virtual memory and the reference implementation of TCP/IP
• Berkeley Software Design, Incorporated (BSDI), The FreeBSD Project, and The NetBSD Project, which continue the work started by the CSRG
The first version of the UNIX system was developed at ...