Just to be clear, Linux is not Unix (in fact, that's what the name Linux means-- Linux Is Not UniX). Linux was modeled after Minix, which was a new OS inspired by System V (although with some fairly significant differences).

True although that many commands are similar and some aplication will rund on linux like apache for example dosent mean that its all the same sorry about that cheef i didnt want to create any confusion ...



later

THANKYOU chort!!! I know this women who used to be a programmer and they used unix and whenever I said that I've been using Linux a lot lately, she would try to correct me and say that it was Unix. I wasn't 100% sure so I didn't say anything, I have heard that Linux is sort of a "Best of Breed" Unix operating system. If what you say is true (which is great ) then I'm gonna tell her about that! I pretty much trust what you say since you are a moderator but can anyone else validate that? Also, what exactly is FreeBSD and OpenBSD based on? Is it something of it's own or what? and where is it headed? (does it's future look really promising???)

No, Linux is not "best of breed" Unix (that's a really odd label, I've never heard that any where). Since Linux isn't Unix at all, it can't be a "XXXX Unix" anything.

Examples of Unix are: AIX, HP-UX, Irix, and Solaris (there are some others I'm missing). All of those operating systems were built on original Unix code (generally System V).

Of the free operating systems, BSD is the most like Unix, because it was actually an improvement of the original Unix code. Way back in the day AT&T used to let universities have the source code for Unix (I think that was Sys III at the time). When AT&T stopped improving Unix, the unversities (University of California at Berkeley, in particular) started taking the code and making significant improvements to it.

Eventually UCB started distributing their BSD code, and AT&T took notice and sued them. The only problem was, AT&T (and many of the proprietary operating systems built on Unix) had been quietly taking BSD code and rolling it into their own operating systems (which they were free to do), except for the rather large fact that they removed the UCB copyright notices.

By the time of the suit, BSD was very popular and several versions had been released. Much of the Internet was being run through BSD machines since they had the best TCP/IP stack implementations. The suit by AT&T made a lot of people fearful of BSD's future, so things started moving in other directions (such as Linux, which I'll get to in a moment). After the suit was resolved (or maybe it was before, I forget) the people from UCB left and started a company called BSDi, which sold BSD as a commercial operating system (BSD/OS).

When BSD became commercial, two groups took the 4.4BSD code and started new OSs, FreeBSD and NetBSD. The FreeBSD folks wanted to make BSD work great on the PC (i386) platform (traditionally Unix and it's derivatives ran on SPARC, Alpha, and other proprietary hardware) while the NetBSD folks wanted to support as many platforms as possible. Some time later the maintainer of the SPARC portion of NetBSD had a disagreement and left to start OpenBSD (which focuses more on security).

So there you have it, BSD is a very close relative of Unix and actually has common source code from Unix (although the UCB coders replaced much of it). Also, a whole lot of utilities and commands from BSD worked their way into other modern OSs, like Solaris (and even Windows uses the BSD TCP/IP stack).

So back to Linux, around the time the BSD folks were making their improvements to Unix, a professor in Europe (errm, Holland I think) decided he wanted to write and OS to help teach programming to his students. He used a lot of Unix reference material and copied some of the Unix concepts to create Minix, which was original released under a restricted license.

Here's where a fellow named Linus Torvalds comes in, because he liked Minix but didn't like the restricted license, so he set about to write his own free OS for the PC using Minix as a loose reference. Linus was later quoted as having said that he was totally unaware of BSD's free status and would have used that instead of writing his own OS from scratch, but he didn't know about BSD and the rest, as they say, is history.

So really, Linux is about as un-Unix as you can get, aside from Windows. Sure most Linux distributions import a lot of commands and utilities from the BSD world, but remember that Linux is only the kernel, not the full OS. Linux is copied from a copy of Unix, so it's similar to Unix is abstract ways. Of course it has become more like Unix is many ways since so many of the companies that sell proprietary Unix OSs have started committing code (like IBM and SGI).

Now back to your question, it's entirely possible that this women you're talking about was a programmer a very long time ago and is not aware of recent developments in the last several years. In that case she might think you just heard "Unix" wrong.

Since we are on the subject of Linux and Companies here is good article:

http://news.com.com/2008-1082_3-5065...g=fd_lede2_hed

I'll certainly back chort up with what I know, he knows much more about BSD than myself but the Unix vs Linux thing is correct. One of the reasons that "Linux" operating systems seem so Unix like is actually due to the development of the GNU utilities. GNU was founded by Richard Stallman to create free (free as in freedom not price) software that had the same or more functionality as the Unix tools that many systems administrators were used to at the time.

One minor correction:
I think you mean Linus

Linux = Linux Is Not UniX

Bah, how did that slip in there? I claim sleep deprivation