I know Linux is an operating system but I see memes and posts about people arguing whether UNIX is an operating system or a kernel and stuff like that. So what separates the two? And what exactly is a kernel?
In: Technology
Unix was written in Bell labs by Kent Thompson and Dennis Richie in 1969, Linux was written by Linus Torvalds in 1991. They are just two separate pieces of software, written by different people. Although I can understand the confusion, Linus specifically made his os as similar to Unix as he could in terms of how it worked and how the user interface was, because by 91 Unix was the gold standard of operating systems.
Of course, both operating systems have evolved a lot since they were originally written, but still, those very first design decisions made decades ago are still very relevant today.
Unbelievably enough, there is a copypasta that answers your exact question perfectly. I don’t know what the odds are, but it happened anyway. Here goes:
I’d just like to interject for a moment. What you’re referring to as Linux, is in fact, GNU/Linux, or as I’ve recently taken to calling it, GNU plus Linux. Linux is not an operating system unto itself, but rather another free component of a fully functioning GNU system made useful by the GNU corelibs, shell utilities and vital system components comprising a full OS as defined by POSIX.
Many computer users run a modified version of the GNU system every day, without realizing it. Through a peculiar turn of events, the version of GNU which is widely used today is often called “Linux”, and many of its users are not aware that it is basically the GNU system, developed by the GNU Project.
There really is a Linux, and these people are using it, but it is just a part of the system they use. Linux is the kernel: the program in the system that allocates the machine’s resources to the other programs that you run. The kernel is an essential part of an operating system, but useless by itself; it can only function in the context of a complete operating system. Linux is normally used in combination with the GNU operating system: the whole system is basically GNU with Linux added, or GNU/Linux. All the so-called “Linux” distributions are really distributions of GNU/Linux.
Others have explained the rest. You got it messed up. Linux is just the kernel which distros (which you call linux) are built on.
I’ll start at the beginning: hardware wasn’t always the same from computer to computer. In fact each major vendor had entirely different hardware and very different ways of doing things. Unix was a set of programs that did typical stuff like changing directories, listing the files, etc. that all computers needed to do. They all had to have their own kernel to talk to their specific hardware. I mean… they all had their own processors and everything! It became cost prohibitive for these companies to maintain such software. So they adopted the standard set of tools. I’m going to hint at “open source” here..
Enter a grad student in Munich named Linus. He wrote a kernel, Unix (posix, really) compliant, for general purpose IBM clone hardware… called it Linux. Pretty cute. That hardware, pretty close, owns 100% market share, now. Linus hasn’t stood still and has adopted his kernel, of course. He’ll go down as one of the most influential software developers of all time. He and his team also wrote git, because they were peeved at centralized source control systems… that’s a particular breed of person with guys like that, Stallman, etc. I’m talking hallowed software guys here. True pioneers. These guys would write a tool because they thought the exercise would be fun and because it might save them time and money later. They published it as “open source”. Anyway…
So what does a kernel do? There’s a solid definition of a few technical things like manage memory, boot, communicate with hardware via firmware, schedule processes with the processor, prioritize jobs, handle interrupts, etc. It does NOT do much you’ve ever dealt with. It’s very low level. All the stuff you’ve ever seen likely resides in the tools on top of the kernel.
I digressed a bit into open source because the OG Unix machines were hundreds of thousands of dollars. Open source democratized computing, Linux democratized server hardware and really helped birth the Information Age. Kinda cool.
I’d like to drop a link to the awesome work done by Asianometry on this topic:
The Rise of Unix: [https://www.youtube.com/watch?v=HADp3emVABg](https://www.youtube.com/watch?v=HADp3emVABg)
A Chronicle of the Unix Wars: [https://www.youtube.com/watch?v=Ffh3DRFzRL0](https://www.youtube.com/watch?v=Ffh3DRFzRL0)
UNIX came first, but it cost money, so a guy named Linus made Linux, which is very very similar and almost as good. Everyone started using it because it was free, which meant it got better and better to the point where no one really cares about UNIX anymore.
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