
The BSD family of operating systems date all the way back to the 1980s when AT&T owned the legal rights to the OS known generically as "Unix". During that time, the source code was licensed out to a few communities, each of which developed their own proprietary version. One of the versions was BSD-Unix, named after the University of Berkeley. Due to license agreements with AT&T when Berkley tried to release their BSD-Unix for free, AT&T sued. The outcome of that lawsuit was the creation of BSD/OS, which was basically AT&T/BSD Unix with the proprietary AT&T code removed. Later on the commercial BSD was branched into what is today
FreeBSD. FreeBSD currently runs on the Intel and Alpha architectures, with ports to Arm, Itanium, PowerPC and Sparc on the works.
I followed Eugenia's link to the main site and 4.5-mini.iso and 4.5-disc2.iso are there, and from the looks of it have finished uploading, but if you look in the md5sums those are the only two cds listed. I hope they finish uploading all of them, but i'm not sure they will until next week. The images that are up there are the mini bootable version of the os on a single cd and a fix it cd, so they might have been able to finish those images before the final release version is done.