Linux is one of the most used systems in the world, operating at the core of most internet servers down to all Android phones and Chromebooks.  It is a clone of Unix, which inspired much of today's computing devices in one way or another.  Outside of computer experts, most people use the term "Linux" to refer to a Linux based operating system for their laptop, desktop, or other devices.  These add a layer of GNU software atop the Linux device, and often have a final layer of another project's interface, such as KDE for desktops, or even a closed source layer like Sailfish OS on a watch.  Because GNU is a common fundamental layer (you can think of it as carpeting or tile in a bare building), some people refer to Linux as GNU/Linux.

GNU/Linux is an open source operating system that is free in more than one way. In a GNU/Linux system, Linux is not an operating system unto itself, but rather the kernel of a fully functioning GNU system made useful by the GNU corelibs, shell utilities and vital system components comprising a full operating system  as defined by POSIX. 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. Because the Linux kernel alone does not form a working operating system, we prefer to use the term GNU/Linux to refer to systems that many people casually refer to as Linux.

Most relevant to community-minded Davis is the philosophy that drives GNU/Linux development: (1) you should be able to know exactly how your operating system works, (2) you should be able to change it if you don't like how it works, and (3) you should be able to freely share it with others. It's no surprise that the DavisWiki is served off a GNU/Linux machine. GNU/Linux users have immense freedom of choice in their software. For example, Linux users can choose from a dozen different command line shells and several graphical desktops. This selection is often bewildering to users of other operating systems, who are not used to thinking of the command line or desktop as something that they can change.

GNU/Linux is also less likely to crash, better able to run more than one program at the same time, and more secure than many operating systems. With these advantages, GNULinux is the fastest growing operating system in the server market. More recently, GNU/Linux has begun to be popular among home and business users as well.

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.

Whether you use GNU/Linux or not, please don't confuse the public by using the name “Linux” ambiguously. Linux is the kernel, one of the essential major components of the system. The system as a whole is basically the GNU system, with Linux added. When you're talking about this combination, please call it “GNU/Linux”.

GNU/Linux is freely downloadable online (e.g. see options on and allows you to run a treasure trove of high quality free software applications. The software most useful to the academic community (office suites, mathematics and statistics, and Internet communications) is well represented, and some recent distributions of the OS have gotten so user-friendly that 9 out of 10 grandmothers can use it.

The computer science major at UC Davis is very Linux/Unix centered. As such, many students taking CS classes run some variant of GNU/Linux on their machines so they don't have to live in the dungeon. OS X also works for this purpose.


  • LUGOD (Linux Users Group of Davis) — learn more about how you can use Linux, or how you can contribute to the local Linux community, or attend one of their meetings. As a testament to Linux's popularity in Davis, LUGOD boasts one of the highest memberships in the nation—not to mention one of the most active.
  • Installfests — an all day event to help you install Linux on your system
  • Professor Matloff's Unix and Linux Tutorial Center
  • The UC Davis CSE department offers an open source software mirror


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2009-01-07 23:21:40   I just put Ubuntu on my parents (and grandparent's) computer. No problems. —CodyDuncan

2011-01-27 09:03:59   I can recommend [Puppy Linux], its a lightweight linux distro that can run from a usb stick and run on old computers -