Today, only the Linux operating system is relevant for computing. It's by far the most advanced workstation, server and embedded platform and provides the best performance, the highest security standards and is supported by all companies. The only disadvantage of Linux is, that from a historical point of view it is not able to tell an interesting story. Linux was invented in the mid 1990s that was a time in which computing has entered the mainstream and all the adventures were done. That means, Linux never explored something which is new, but it's only an efficient Unix clone in combination with the X window system.
If somebody is interested in the history of UNIX in the 1980s, Linux is a bad starting point because in that area Linux was not invented yet. The more elaborated starting point is to focus on the BSD operating system, which is sometimes called the true Unix system. Today, the BSD Unix operating system is nearly obsolete. On most real hardware it's no longer used and was replaced by modern Linux systems. But in the 1980s the situation was the other way around. Getting familiar with the Unix culture is equal to understand the BSD system.
In the 1980s, computing was looking different from today's approach. The Internet was something which was brandnew, and getting access to a 32bit workstation was a valuable resource. In the 1980s, programming software and creating Postscript documents was done only by the academic community. It's fascinating to take a look back and explore what the pioneers have done. All the technical improvements which results into the modern Internet was done in the 1980s. It was the time in which fast CPUs were designed the first time, huge harddrive have become cheap, and 24/7 server operating systems went online for the first time. The 1980s in combination with the UNIX was also the first time, that the end user was in the position to typeset academic documents with the TeX and the troff package. And everything was new and exciting.
To understand the relationship between Linux and the BSD operating system in detail, a short look into a paper from the mid 1980s make sense in which the BSD Unix system was introduced. In the 1980s many academic paper were written about the subject because the researchers and enthusiasts were interested in the new features of a time sharing operating system. They were proud to describe features like the TCP/IP protocol, the terminal for realtime access to the minicomputer and in some cases, the X Window system was described briefly. For the 1980s the subject was remarkable advanced. And it was right to cover the topic of UNIX in academic papers.
The interesting point is, that today in the 2010s nobody would write such papers, and especially not about the Linux operating system. The reason is, that Linux is nothing which is new. It's interesting to see that the latest Ubuntu version provides also the X window system, a terminal and is provided with server capabilities but from an academic standpoint this technology is obsolete. It was innovative 30 years ago. The Linux operating system has produced some kind of paradox. On the one hand it's the most advanced piece of software which was ever invented. It runs on nearly all sort of hardware and provides a lot of powerful tools. Programs like the Lyx publishing tool, the Python programming language, and of course the Gnome environment are very powerful elements of Linux. The only problem is, that the enduser isn't surprised anymore but he assumes that such features are normal. That means, nobody gets excited if an operating system is able to run 10 applications in parallel without an error message, and nobody is impressed if the Python interpreter runs a GUI without any problems.
Without any doubt the BSD OS is obsolete. The original BSD distribution isn't available anymore and the later developed FreeBSD package can't compete a modern Linux distribution. The problem is, that if BSD Unix is obsolete the danger is high that Linux can be labeled with the same term. Sure, Linux can be used to boot a current PC into the graphical mode and new programs for the Linux OS are developed each month. The problem is, that there is nothing which is new. A powerful multiuser operating system can be invented only once, and then all the new versions will look like a clone. The only thing what can be explored today is the history of UNIX. That means, in which year the first version of the X Window system was invented, and what the Unix wars in the 1980s were about. The look back into the past is unexplored land. Some stories were published already but there are many unexplored areas available.