Linus Torvalds announced the first version of Linux in 1991, but some Linux concepts are even older than Linux itself.
While Linux is generally considered a modern operating system, some of the concepts are much older than you might think. The following are some concepts that have a long history in Linux systems.
Using dual-boot has been the standard way to share Linux between different operating systems, including Windows. The concept of a multi-boot operating system is almost as old as computers.
It is also popular in Unix-like environments, such as running Unix and MS-DOS on older PC Unix systems such as Xenix. Dual boot was also implemented on the Amiga before Linux.
The Commodore Amiga 3000UX comes with Amiga Unix, a customized version of System V, and the standard Amiga Workbench operating system. You can select the operating system at boot time by using the left and right mouse buttons.
When Linus Torvalds released the Linux kernel on Usenet in 1991, he himself did not foresee that it would expand to other architectures besides the Intel x86 platform, but he probably should have left history with such a precedent.
Like the original Unix, Linux is written in the C language. C itself is a portable language. As long as a C program makes no assumptions about the underlying environment, it can be compiled on any computer, as long as it has a corresponding compiler.
Like many operating systems of the time, Unix was originally written in assembly language, but Dennis Ritchie rewrote it in the C language he invented in the early 1970s. A side effect of this was that the operating system was decoupled from the hardware and Unix became a general-purpose operating system.
This was unusual at the time because the operating system was tied to a specific machine. This is one of the reasons why Unix made such a splash in computer science circles in the 1970s and 1980s.
The Bash shell is the popular default shell on Linux systems, but you can easily change your login shell to any shell of your choice. You probably know that this is a feature of the original Unix systems, but did you know that the idea is even older than Unix?
DEC is developing an operating system called MICA that will run on a new processor architecture called PRISM. It will be based on DEC's popular minicomputer operating system VMS, but will also have a Unix flavor.
This ambitious project is the brainchild of Dave Cutler. DEC eventually canceled the MICA project, and Cutler moved to Microsoft to lead the project that would eventually become Windows NT.
On the VMS side, there is also a program called Eunice, which can also run Unix programs. Like the original WSL, it works, but it also suffers from performance and compatibility issues compared to native Unix.
When Windows NT finally came out in 1993, it had a POSIX environment, but seemingly only so that Microsoft could say it was POSIX compliant and bid on certain contracts with the U.S. federal government.
Microsoft will also release a more complete environment-Windows Services for Unix, and the open source Cygwin project will also appear.
In the early 2000s, the lawsuit filed by SCO against IBM received widespread attention in the Linux and open source communities. SCO claimed that Linux infringed on their rights to original Unix code, which they had acquired ownership of.
While IBM and the Linux community ultimately prevailed, this situation had precedent in the original Unix days. AT&T's Unix System Laboratories (USL) claimed copyright on Berkeley's software distribution code, which put pressure on Berkeley in the early 1990s.
Linux became the darling of computer enthusiasts, although it turned out that only a small number of files were "restricted" and could be easily rewritten for open source distribution.
Although the Linux community likes to argue about which distribution is better, this is nothing new to Unix culture.
In the 1980s, the debate between AT&T's System V and BSD was a big deal. The latter is more popular in academia and was developed at the University of California, Berkeley. It is also a major component of workstation Unix, such as Sun Microsystems.
By the late 1980s, the Unix world was mired in the so-called "Unix Wars." AT&T and Sun began working together to merge BSD and System V, which alarmed other computer companies such as Hewlett-Packard, DEC, and IBM. These companies later formed the Open Software Foundation, and Sun and AT&T formed Unix International.
This "war" finally ended with a ceasefire. The two organizations merged, but Linux eventually replaced proprietary Unix in most applications.
Linux distributions are known for their desktop user interfaces and are designed to make Linux accessible to non-technical users. This effort also has a long history, as can be seen in the 1989 PBS television show The Computer Chronicles.
In the show, we can see products from Sun Microsystems, HP and even Apple. Apple has also launched a Unix-based operating system A/UX.
Although Linux popularized the concept of open source software, the idea has been around for a long time and may have existed in computers themselves.
Although the GNU project gained its reputation for its clear philosophy of providing free software, the software has long circulated freely in academia. BSD developers created their own license allowing free distribution.
You might be surprised how old some concepts in Linux culture, such as dual boot and open source software, are. Much of Linux's special features can be explained by its origins in Unix.
One example that confuses many people new to the Linux command line is that the commands look strange. Why are they so short? The reason is that they were originally designed for teletypes, not screens.
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