What exactly do we mean when we say we are using Linux?
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.
I always thought Linux as a kernel and Operating System but it looks like Linux = Linux kernel and GNU OS. Could someone point out the exact functionality of each in the «Linux» terminology we use in our day to day life. Also, according to the wiki, GNU’s design is Unix-like but differs from Unix by being free software and containing no Unix code. I thought Unix is opensource. Isn’t it?
3 Answers 3
I believe the bit you’re referring to is covered here on the Free Software Foundation (FSF) website:
According to the FSF their contention is that Linux is just a Kernel. A usable system is comprised of a Kernel + the tools such as ls , find , shells, etc. Therefore when referring to the entire system, it should be referred to as GNU/Linux, since the other tools together with the Linux Kernel make up a complete usable system. They even go on to talk about the FSF Unix Kernel, Hurd, making arguments that Hurd and Linux are essentially interchangeable Kernels to the GNU/X system.
I find the entire argument tiring and think there are better things to do with our time. A name is just a name and the fact that people consider a system that includes GNU software + the Linux Kernel + other non-GNU software to be Linux or GNU/Linux a matter of taste and really doesn’t matter in the grand scheme of things. In fact I think the argument does more to hurt Linux and GNU/Linux by fracturing the community and confusing the general public as to what each thing actually is.
For more than you ever wanted to know on this topic take a look at the Wikipedia articled titled: GNU/Linux naming controversy.
All Unixes opensource?
To my knowledge not all Unixes are opensource. Most of the functionality within Unix is specified so that how things work is open, but specific implementations of this functionality is or isn’t open depending on which distro it’s a part of.
For example, until recently Solaris, a Unix, wasn’t considered open source. Only when Sun Microsystem’s released core components into the OpenSolaris project, did it at least components of Solaris become open source.
Unix History
I’m by no means an expert on this topic, so I would suggest taking a look at the Unix Wikipedia page for more on the topic.
Linux History
Take a look at the Unix Lineage diagram for more on which Unixes are considered open, mixed, or closed source.
I also find the GNU/Linux Distribution Timeline Project useful when having this conversation.
No UNIX is open source and Linux is not Unix. Unlike FreeBSD, which is a direct descendant and once contained ATT UNIX code, Linux has no direct connection and is only Unix-like. OSX is UNIX.
@Rob FreeBSD no longer contains ATT code: that’s what made it free. It doesn’t have more or less claim to the name Unix than Linux or MINIX or OSF/1.
@Rob — please site references. I’m sure you don’t mean that comment to come across as sounding like a troll, but it is, at least a bit 8-).The whole is Linux a Unix debate has been covered here already. Please see this thread: unix.stackexchange.com/questions/4091/is-linux-a-unix. I find that argument tiring. It’s like argument how to pronounce tomato.
@slm I only responded to your comment that «Not all Unixes are open source» and the truth is no Unixes are open source. UNIX is a trade name, a validation and certification. It also means there is POSIX compliance to a degree Linux and other systems can’t validate (but OSX can). I wasn’t arguing anything except UNIX is UNIX and Linux is not UNIX which your post seemed to say, iirc. (I was not aware of previous thread, or any other.
Typically, what we usually call an Operating System, is a combination of software involving a kernel, whose job is to manage the resources of the machine and some applications that run on top of the kernel, called the userland (this contains browsers, compilers, pdf readers, anything that isn’t the kernel, or a driver, or maybe a vm hypervisor).
The rest of this question can not be answered without some historical context. Richard Stallman anounced the GNU Project on the 27th of September of 1983. The aim was to provide the software needed to develop a UNIX like operating system (and the accompanying userland) as free software. By 1992, the GNU Project had completed nearly all pieces essential for their software — except for one: the kernel. By the same time, Linus Torvalds released his kernel Linux (version 0.12) as free software, licensed under the GPL license. So for the first time, it could be possible to run a computer comprised (nearly) entirely of free software.
Linux (as mentioned) is a kernel, and, although it’s the ultimate base of the software that allows you to use your computer, it’s not of much usefulness alone. You should pair it with some sort of applications (userland) for it to run. That’s what GNU/Linux distributions like Debian or Ubuntu and the like do.
It’s worth mentioning that a kernel is both important and unimportant at the same time. Allow me to explain. Most people that use a computer are accustomed with the userland rather than the kernel. The kernel is mostly transparent, and most people would use another kernel with the same userland and might not even notice the difference (unless of course they are depending on a feature provided by a particular kernel).
Therefore, when you use Linux, you trully are using a realisation of the GNU operating system; that is the Linux kernel and the GNU userland (GNOME, GNU Compiler Collection, GNU debugger, GNU Coreutils, GNU binutils, etc). That’s why the FSF insists on calling it GNU/Linux (in my opinion, a fair request).
You can of course, use Linux without the GNU userland (hint: Android, Busybox) and ofcourse use the GNU userland on top of other kernels (kfreebsd, hurd, etc).
As for the Unix is open source and the like, that is a question that can involve quite a bit of arguing. You might however find some useful information here
What is GNU/Linux Copypasta?
As a Linux user, you might have come across a long text that starts with “I’d like to interject for a moment. What you are referring to as Linux, is in fact, GNU/Linux”. It makes some people confused about what is Linux and what is GNU/Linux. I have explained it in the article about the concept of Linux distributions. Basically, Linux is a kernel and with GNU softwares, it becomes usable in the form of an operating system. Many purists and enthusiasts don’t want people to forget the contribution of GNU to the Linux-based operating systems. Hence, they often post this long text (known as GNU Linux copypasta) in various forums and communities. I am not sure of the origin of the GNU/Linux copypasta and since when it came into existence. Some people attribute it to Richard Stallman’s article on GNU blog in 2011. I cannot confirm or deny that.
Complete GNU/Linux Copypasta
I’d just like to interject for a moment. What you’re refering 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!
What is a Copypasta, again?
Did you notice that I used the term ‘copypasta’. It has nothing to do with Italian dish pasta. Copypasta is a block of text which is copied and pasted across the internet, often to troll or poke fun at people. It is a degeneration of the term ‘copy-paste’. Copypasta is also considered spam because they are repeated as it is a number of times. Take the example of GNU Linux copypasta. If a few people keep on pasting the huge text block every time someone uses Linux instead of GNU/Linux in a discussion forum, it would annoy other members.
Have you ever used GNU/Linux Copypasta?
Personally, I have never done that. But, to be honest, that’s how I come to know about the term GNU/Linux when I was a new Linux users and was browsing through some Linux forum. How about you? Have you ever copy-pasted the “I would like to interject for a moment” in a Linux forum? Do you think it’s a tool for ‘trolls’ or is it the necessary evil to make people aware of the GNU project?
What you are referring to as linux
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Incorrect Quotation
A quotation circulates on the Internet, attributed to me, but it wasn’t written by me.
Here’s the text that is circulating. Most of it was copied from statements I have made, but the part italicized here is not from me. It makes points that are mistaken or confused.
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.
The main error is that Linux is not strictly speaking part of the GNU system—whose kernel is GNU Hurd. The version with Linux, we call “GNU/Linux.” It is OK to call it “GNU” when you want to be really short, but it is better to call it “GNU/Linux” so as to give Torvalds some credit.
We don’t use the term “corelibs,” and I am not sure what that would mean, but GNU is much more than the specific packages we developed for it. I set out in 1983 to develop an operating system, calling it GNU, and that job required developing whichever important packages we could not find elsewhere.