The UNIX system has been in wide use for over 30 years and has helped to define many areas of computing. Although numerous individuals and organizations have contributed (and still contribute) to the development of the UNIX system, this book primarily concentrates 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
• The FreeBSD project, the NetBSD project, and the OpenBSD project, which continue the work started by the CSRG
• The Darwin operating system at the core of Apple's OS X. Darwin ...