Common Questions and Misconceptions

There is no generic Linux FAQ (frequently asked questions), so let's gather some of the most common, often-repeated questions about the operating system and social movement here and in sub-FAQs.

Remember, put general stuff only in the FAQs! All other questions should go to the forums. Of course, more detailed topics and todo's go in other pages of the Wiki.

General

Q: What is Linux?

A: See Wikipedia

Operating systems

Q: What makes Linux different from Microsoft Windows?

Linux is oriented towards developers rather than users
Linux is a Unix clone
Linux is free. This has several advantages
- you do not pay money
- you accidentially ordered the wrong language - With a commercial OS, you can buy again, with Linux it is a matter of installing a language.
Linux is Open source
Linux is written by volunteers, Windows is created by a company
Linux comes with a lot of useful software, e.g. OpenOffice is already shipped with SUSE
Linux is secure
Linux is available for many platforms

Q: Is Linux the only Open Source operating system?

No. There are other open source operating systems(OSs). Most are based on UNIX. The most popular and readily available open source OSs are Linux and the variants of the Berkeley Systems Division (BSD) OSs, including: Free BSD, Net BSD, and PC BSD. There is also OpenSolaris, a descendant of Sun Microsystem's operating system, however, OpenSolaris is still under construction.

It's worthy to note that the Apple Macintosh OS X, although a commercial OS, is also a UNIX-based OS, derived from BSD.

Therefore, those of us running Intel architecture based personal computers have 2 main choices: Microsoft Windows or UNIX (whether that be Linux, BSD, Mac OS X, or OpenSolaris).

Q: What does Linux look like?

As explained in another answer, you can have several 'Graphical User Interfaces' (GUI) on Linux. A GUI is software that provides the user with windows, dialog boxes, a desktop, menus, buttons to click, etc. For Windows the GUI is 'part of the system' and people don't make the distinction between GUI and Operating System. Under Linux and Unix, the GUI is just another application, so you can choose whatever you want. GNOME and KDE are popular. They are both very much customizable, i.e. you can modify color schemes, window behavour, etc. So it can be made to look like Windows XP, or not.

GNOME and KDE are considered Desktop Environments, as they include many different utilities common for a computer desktop. Another desktop environment, which is not as fully-featured (and usually runs a little faster) is called XFCE.

Apart from these Desktop Environments, there are a number of so-called 'Window Managers' - not complete desktop environments such as GNOME and KDE, but more rudimentary applications that provide windows etc for user interaction.

So, in short : what does Linux look like? Linux will look exactly how you want it to look.

Q: Is Linux compatible with Windows?

Not really. You can't natively run Windows applications on Linux or Linux applications on Windows. But there are emulators like Wine, Win4Lin, Cedega and CrossOver which you can use to run Windows applications on Linux. Linux can mount Windows FAT32 and NTFS (experimental) partitions and also share files between Windows on a network using Samba. Many file types can be used with both, such as doc and PDF files. For most applications running on Windows, there's Linux-Windows equivalent software.

Q: Is Linux really more secure than Windows?

When we compare operating system security, the leading questions are 'Can the system be exploited over the network? Could the operating system cause legal problems? Is the operating system safe from the user?'

Linux is generally safe right out of the package. SELinux is even more safe, but flexibility and ease of use are compromised.

There are several tools that run on linux, which report any security holes. Saint is one. This makes it easy to seal up a system against outside attacks. There are, however, heavy penalties for destroying computer data. Thus, even if an attacker does secure administrator privileges, they generally do not destroy data.

Users of both operating systems must be aware that NOTHING they transmit over an unencrypted interface is "private".

Q: Why Open Source?

Open-source software is required to have its source code freely available; end-users have the right to modify and redistribute the software, as well as the right to package and sell the software. The Free Software Foundation's definition of free software goes further; as a consequence of this, free software is open source, but open-source software may not be "FSF-free".

The FSF intends the word "free" to mean "free as in free speech", not "free as in free beer". By saying "open source" you make clear that you are not talking about free (gratis) software but about software that preserves the "freedom" to modify its source code.

Q: Which Windows users should switch to Linux? Why?

Anyone can switch to Linux, provided they want to learn and are ready to accept changes. Why? There are lots of reasons. You might hate Microsoft and its policies, hate the insecure environment of Windows or you might want freedom from restrictive proprietary licences.

Linux distributions

Q: Is Linux really available for zero cost?

Yes and No. Yes, you can download off the internet almost any distribution of linux free of charge. However, like any software, it can be bought from a retailer. Mandrake Discovery 10.1, for example, can be bought from mandrakesoft.com for $45. Buying an official package most often gives technical support from the company.

The Free character of linux is often misunderstood. As Richard Stallman, the founder of GNU and the most famous promoter of free software said, "Free taken as in free speech, not free beer."

You can go to distrowatch.com to find and get a large number of linux distributions.

Q: Cost of acquiring knowledge about Linux?

The cost of aquiring knowlege about Linux varies depending on how fast you want it and what kind of a commitment you want to make. Some people learn their way around Linux simply by using it as their primary desktop. With a good year of use, a person can have a fair knowlege of the operating system, enough to handle most things they want to do on a regular basis.

However, there are a number of books out there that can help you learn to use Linux much faster than simple experience can.

Finally, many IT jobs involve working with Linux servers. This is probably the best and fastest way to learn to use Linux, because there are tasks you are required to complete, so you must learn how to do them, and you are immersed in the operating system, ensuring that what you learn is put into practice.

This is not just for Linux. Windows itself has a cost to acquire the knowledge. Because, however, most of us end up seeing Windows at school, we are already familiar with it, and so generally is considered to not have an actual cost of acquiring the knowledge. One interesting point to note is that many companies will not upgrade to Office 2007 when it comes out because of the cost of learning the new way it works. Many companies seem to delay upgrading until whenever they can and then jump several versions to minimize the cost of re-testing the software and re-training the staff.

Q: What is a distro/distribution?

Linux is not what you sit in front of your computer and use. "Linux" in it's strictest sense is merely the base "kernel", that is, core bit of software that everything on your computer running on Linux interacts with. Everything else are "packages", collections of software. Window managers programs are packages, and it is the collection of packages that defines a distribution. Some people want a version of Linux bundled with a heaping load of packages to do everything under the sun out of the box. Distributions like Suse and Fedora cater to that. Other people want a distribution that's especially lightweight, containing nothing but what they need. Distros like Vector and Puppy Linux cater to those people.

A distribution is just a bundle of software that is placed on top of the Linux kernel. There are other differences between distros, though, such as Debian's apt-get system, but that, too, is a sort of program.

Q: I want to try it. What distribution should I use?

Main article: Choosing a Linux distribution

You can start by

Installing VMWare, create a virtual machine and install Linux there

This will allow you to run Windows and Linux in parallel and is clearly the best way to start.

Booting from a Live CD, e.g. Knoppix.

This will boot Linux, but not install it to your hard disk. However, you will not be able to change files.

Installing Linux to a USB disk.

This is like the Live CD approach, but you can change files on the disk.

As a beginner's distribution you can choose SUSE or Ubuntu. If that is not enough choice for you, see the List of Linux Distributions. If you want to know what can distinguish Linux distributions, see Distro Differences.

Linux kernel and desktop

Q: What are KDE/GNOME and why are there two of them?

see : what does Linux look like?

KDE and GNOME are desktop environments that look very similar to Windows. They interact with Linux through the X WindoWing system, which is a very robust and configurable windowing system. The X server runs on top of Linux, which means that it is optional to the running of the operating system. Without it Linux looks like the command prompt in DOS.

Unlike in Windows, the command prompt, or shell in Linux is still very useful. There are a lot of applications that run without X. There are also a lot of things that can be done more easily without the use of graphical tools. Linux is all about choice, and there are many ways to change the look and feel of your computer.

Linux problems

Q: Where can I get support for Linux?

Point your favorite IRC program to irc.freenode.org, join the channel of your distribution like #suse or #fedora. There you can have a live chat and ask as well as answer questions.

Q: Linux feels slow - why?

Linux does not feel slow on a reasonably modern computer. If your Linux feels slow, you have the choice of buying a better computer or do tuning. For tuning, it is necessary to first find out the bottleneck that limits your performance, have a look at diagnostics for doing this. If your bottleneck is RAM, you can decide to go for a more lightweight Window Manager, e.g. choose Window Maker instead of KDE in the login screen. There are even distributions that are optimized towards performance - however every distribution can be tuned to deliver the same performance.

Q: How can I get a directory's size?

This is a major problem of Linux file systems - it is not possible. However, there are programs that read all files in a directory and add their sizes, so you can find out the directory's size. Here's an example:

ls -1 | xargs du -sh

This shows you all directories with their size.

Q: Why is Linux using up all my memory?

Q: With programs like xosview, free and top I can observe that Linux has a small memory footprint after booting and this gets larger and larger while running. Why is this so?

A: You have to make a distinction between cache and user memory. When Linux reads a block from the hard disk, it keeps this block in memory until the memory is required otherwise. We say, it caches the block. By doing this, the system gets faster - it does not longer need to read the hard disk for this particular block, it is enough to access memory. And memory access is much faster than disk access. This is why in a "well warmed up" system, you see huge caches:

# uptime
  8:49am  up 13 days 20:48,  10 users,  load average: 0.36, 0.27, 0.27
# free -m
             total       used       free     shared    buffers     cached
Mem:          3956       3922         33          0         38       2834
-/+ buffers/cache:       1050       2906
Swap:         9765        474       9290

The system may even swap cache from memory to disk. The tendency to do so is set by the swappiness setting.

Linux HOWTOs, FAQs, docs, tutorials, man pages, guides, tips, reference manuals, indexes

Q: Where can I get information about Linux on LQWiki?

A good place to start is the Main Page where you can choose a section related to the question or interests you have about Linux.

Another way is to use the 'Go or Find' part on the right of every page. Just type your subject in the text-area and press the 'Go' or 'Search' button. The 'Go' button sends you to the page with the name of the subject you filed in. If there is no page with that name it will look for pages with almost the same name. The 'Search' button gives you a result of a search in the titles or content of the site. Or choose a topic in the subsystems page.

Q: How do I get from a vague idea to the information I want?

Posting in a forum is a good way to resolve this issue. Many forums --like LinuxQuestions-- have many people who are eager to help you with your problems Simply search in the forum for your problem. If no one else has had the same problem, start a new thread in the appropriate portion of the forum with a descriptive title. Inside the post, put all necessary information. Don't simply say "my printer won't print". Include the make and model of your printer, how it's connected to your computer, how did you set it up, did it ever print properly, etc., . Giving all pertinent information when asking for help is a very good way to increase your chances of resolving the issue.

Q: Where can I get information about Linux on the internet?

You can

search http://google.com/linux
post a question in a forum, e.g. http://www.linuxquestions.org
get help from IRC

There are also Linux podcasts that allow you to get reviews of Linux distros and programs, as well as interviews with prominent open source developers.

Q: Are there any good books about Linux?

Linux Administration: A beginner's guide (4th edition, 2005) by Steve Shah and Wale Soyinka is excellent for those NOT new to administering Windows (e.g., installing applications and new hardware, setting up users, etc.) Available at Amazon.com