Thread: iMac?

BSD is a Unix operating system

AT&T's research division, Bell Labs, developed UNIX in 1969
UNIX was a research operating system, intended to drive innovation

AT&T licensed copies of UNIX to people
When you bought a UNIX license, you got the complete source code to the operating system, and full rights to use, modify the code and redistribute

The University of California, Berkeley bought a UNIX license
they then went about modifying it to suit their needs

They invented the Unix domain sockets (called Berkeley sockets, at the time), the TCP/IP stack, the init runlevel system, and a whole host of other things to enhance the operating system in a fully networked, multi-user environment

BSD is Unix
AIX is Unix
HP-UX is Unix
Solaris is Unix
Xenix is Unix

BSD was an original Unix derivative

Since BSD, and the other Unix derivatives mentioned above, first arrived, a few things have happened

- AT&T sold the rights of UNIX to the Santa Cruz Operation
- The Santa Cruz Operation then sold the rights to UNIX to Novell
- Novell then gave up the rights to UNIX, and transfered all rights & ownership over to the Open Group

With the UNIX rights and ownership now held by a non-profit organisation, UNIX is now open to other non-profit organisations and individuals
(no more licensing)

Free BSD, Open BSD & Net BSD are derived (at varying points) from BSD

The Mac OS X userland is lifted straight from Free BSD
The Mac OS X kernel is the Free BSD kernel (with a few bits & bobs added by Apple)