How many different families of operating systems exist in unix?

I know that Mac OS, Linux, Open Solaris, and BSD are related to Unix, are there any other operating systems that are based on or related to unix? Please don't not include variants of any of that already mentioned operating systems, such as FreeBSD, Or any Linux-based distros.

Also, is there any other family of operating systems separate from Unix?

Last edited by DragonMaster Jay on 25th July 2010, 7:02 pm; edited 1 time in total (Reason for editing : Removed signature.)

TONS OF THEM.

I think there is too many to name. I'm currently running Ubuntu(Linux variant/breed). Ubuntu does pretty well. Are looking to install or learn more about them? Or just curious?