Linux Basics

This article does not cover Linux installation. I assume that the reader has already installed one of the distributions of this OS. However, after successful installation, the user usually has many questions, some of which are answered in this article. In preparing this material, Black Cat Linux 6.02 was used, but everything stated below applies almost unchanged to other Linux distributions (for example, Red Hat or Mandrake).

As you know, you can work in Linux in graphics system X Window or in a text console. Most users prefer to work exclusively with the window manager after installation, but there are a wide range of tasks that can be performed (or are much easier) by working in the console. Therefore, this is where I would like to start this article.
First, a little about setup.

Working with the linuxconf program.
If, when installing Linux, you configured automatic start X-ov, then you need to first go to the console. To do this, click Ctrl+Alt+F1. You will be taken to a virtual text console and after entering your username and password you will be able to issue commands shell. To return to the X Window, click Alt+F7. Generally speaking, by default you can work in 6 virtual consoles at once, which is often very convenient (switching between them is Alt+F1...Alt+F6).
In the console, enter the command linuxconf. The system management program will start. Here you can manage users, network connections, file systems, boot and other Linux settings. The program is organized as a drop-down menu. Navigation is carried out using the arrow keys, Enter And Tab. As an example, we will show how to create a new user and define its rights. Let's go to Config>User accounts>Normal>User accounts
A list of users is shown here. Click twice Tab to go to the button Add, then Enter. In the column Login name In the window that appears, enter the name of the new user. The remaining fields can be left untouched for now. After pressing the button Accept you will be asked for your password twice - and a new user has been created! I advise you to work as little as possible as root, since his mistake can cause the most fatal consequences for the system, while an ordinary user can usually damage only his own files.

Linuxconf is also convenient for describing file systems. For example, let's look at how to "teach" Linux to see the Windows partition. Let's go to Config>File systems>Access local drive. A list of file systems described in the file appears /etc/fstab. To add to it new entry, click Add. In the column Partition we write /dev/hda1 for 1st section hard drive, /dev/hda2- for the second, etc. If you want to add the first section second hard disk - write /dev/hdb1, second - /dev/hdb2. In the column Type click Ctrl+x and select the file system type from the list ( vfat for Windows). In the column Mount point dialing /mnt/win. After clicking Accept answer positively to the question about creation new point mounting. Now in the catalog /mnt you will have a catalog win, which should contain the contents of the Windows partition, but if you go into it, you will find that it is empty. In order to see your Windows partition in it, you need to give the command in the console mount/mnt/win. Among other Linux OS configuration programs, I would also like to note setup, which easily allows you to configure your keyboard, mouse, sound card and X Window.
Working in the console is quite convenient, but to navigate through directories it is much more pleasant to use Midnight Commander.After calling the command mc Norton-like appears on the screen file manager, which is almost as powerful as DN or FAR. Personally, I also use mc to set access rights to files and directories, since it is much more convenient for me to use than the utility chown.

Installing applications under Linux.
For Linux, applications are delivered primarily in the form rpm-packages or .tar.gz-archives. Installed rpm-package by command rpm -i package name
Program rpm It will create all the directories necessary for the application to work and put the files there. If you already have a previous version of the application installed, then you need to provide the key on the command line --force to replace the old version. rpm-packages are available on the CD of most Linux distributions, as well as on many ftp servers on the Internet. If the extension rpm-file looks like .src.rpm, then this is the source code of the application, and before running it you need to compile it yourself (usually such packages contain instructions on how to do this). To remove a package from the system, issue the command rpm -e package name.
If you received the application as a packaged file with the extension .tar.gz, then to unpack it you need to give the command tar xzvf archive name. Next, you need to find a file with instructions for installing the application, which may vary in each specific case.
By the way, to view the contents of archives without unpacking them manually, it is convenient to use Midnight Commander. When pressed Enter on the archive name, you enter it like a regular directory.
I would also like to mention one useful program - fsck. If, for example, while working in Linux you had a power cut or accidentally pressed reset :-), then when you boot the OS will ask for the root password and you will be in single-user mode. In it file system mounted for read and execute only. To repair a damaged file system, issue the command fsck-Aa. After it's finished, give the command reboot, and after a reboot everything should work as before.
To view documentation for any Linux command on the command line, you need to specify: man command_name. The standard documentation viewer will launch and tell you about the usage, switches and configuration files of this command. If the information is not enough, then in the catalog /usr/doc you will find complete manuals to most Linux programs.
Finish review useful programs, launched from the console, I would like document processing utilities. If you have ever tried to read text files created in DOS or Windows in Linux, you must have encountered the problem of transcoding. The fact is that Linux uses KOI-8 encoding, which is different from DOS or Windows. A utility is used to convert text recode. For example, we will show how to convert a file myfile.txt(Windows encoding) in KOI-8:
recode -wk myfile.txt myfile.koi
After executing this command, a file will be created in the current directory myfile.koi, which can be viewed with any text editor under Linux. Key -wk specifies conversion options (Windows - KOI8). There are 14 more possible keys. A list of them with a description can be obtained by issuing the command recode without parameters.
We are also interested in the program mswordview. It is designed to transform doc- files ( Microsoft Word) V HTML- a format that is supported by many editors on Linux. Now you won't need to keep Windows and MS Office on your hard drive just because you need to work with doc-files. By the way, the famous free office suite StarOffice, which runs on Linux, also works great with Microsoft Office files.
Now let's move on to working with X Window. If you don’t have X running by default, then run the command in the console xinit. If everything is configured normally, you will be taken to the graphical console. Next you need to give a command to start the window manager (for example, kde For KDE, or icewm For IceWM). These two operations can be replaced by one - a script startx. If none of the methods discussed above works, it means that your Xs are most likely configured incorrectly, and then you can try to fix it with the program setup discussed above.

There are quite a few window managers for Linux. Some of them claim to be similar to Windows 95 or MacOS, but most still have the original interface. In this article I will talk about KDE- in my opinion, this is the best environment for work. I don’t want to offend amateurs Gnome, but on my machine it runs much slower, which doesn't suit me.
After launching KDE, you are presented with an environment that at first glance looks like Windows. There is a button in the lower left corner TO, similar to a button Start in a well-known OS. At the bottom of the screen there is a taskbar, a clock, and a keyboard indicator. Well, in general, everything is like THERE. But this apparent similarity between the KDE and Windows interfaces will wear off pretty soon. You will see how much more convenient it is to work with the first one.
To begin with, I would advise running the script KAppFinder(its shortcut is on the desktop), which will add to the menu Personal those applications that are not included in KDE (for example, utilities Gnome, Netscape Navigator).
In order to configure appearance KDE, right-click on an empty space on the desktop and select Display Properties. Here you can change the background, screen saver, fonts and display styles of KDE applications.
Shortcuts on the desktop are created similarly to Windows 98, i.e. via menu item New in the pop-up menu. This article looked at how to use the command mount need to mount others sections of hard disk, previously described in the file /etc/fstab using the program linuxconf. In KDE, you can create shortcuts on your desktop that correspond to these sections. To do this, right-click on an empty field of the desktop to call up a pop-up menu. Choose New>System Device File. Give it a name (for example, "Windows"). Go to the tab Device. Here in the column Device set the section (for example, /dev/hda1), and in the graph Mount point- the directory that was specified in linuxconf (in this article - /mnt/win). Count File system leave unchanged. After clicking OK, a “Windows” shortcut will appear on the desktop. Now, in order to get to this partition, you will no longer need to issue the mount command every time. At double click on the shortcut, mounting will occur automatically and you will see the contents of your Windows partition. By the way, I would like to dwell separately on the program that allows you to view catalogs. It's called kfm and launched from the menu System>File Manager. With this application you can not only manage files (like Microsoft Explorer), but also view html-files (which is very convenient when reading documentation), as well as “climbing” through ftp-archives, as if in their own way hard drive. The fact is that kfm has a built-in quite powerful browser that supports various text encodings, working through proxies, cookies and a lot of other things.

We are also interested in the application kpackage- Package Manager. It allows you to install and uninstall Linux applications without resorting to a console utility rpm described above. On the left side of the screen there is a list of installed packages, divided by category. When you select one of them, its description is shown on the right side of the screen.
Now a few words about typing. There are “numerous” editors for this noble occupation in Linux. Some (for example, ed, vi) have remained from THOSE times when people worked at “stupid” terminals and could only dream of X-s. Additionally, Linux comes with a very powerful text editor Emacs, however, more than one article can be written about it. Now I will talk about two editors for KDE - kedit("Simple text editor") and kwrite("Advanced Editor"). I use the kedit editor all the time. It is small, fast and convenient. Allows you to check spelling, align text, open pages directly from the Internet and write them back. Your message can be sent immediately by mail. By the way, a little advice: in order to view the contents of a file in Windows encoding without using the utility recode described above, open this file in kedit and then to the menu Settings>Font select any font whose name ends with "1251". After this, you will be able to see the contents of the file, but you are unlikely to be able to change it.

Editor kwrite intended for typing program code rather than text. It allows you to mark up syntax, make bookmarks and much more that you cannot do kedit. In my opinion, one of its main advantages is the ability to rollback (similar to Undo on Windows).
Finally, I would like to note the program console. This is a graphical terminal emulator. Launched from X and functions as a virtual console. IN console you can enter commands shell or run Midnight Commander. Personally I use console For quick launch in KDE of the required applications. I don’t know about you, but I find it much more convenient to type on the keyboard kmmail, kedit or netscape than clicking on drop-down menus or shortcuts. Just don’t forget to put a sign after the application name "&" , otherwise the console will be locked until you exit it.

What's happened Ubuntu? Ubuntu is a modern, full-featured operating system, based on Linux kernel. Translated from the South African Zulu language, the word Ubuntu roughly means “humanity.”

Ubuntu is and will always be distributed absolutely free. But at the same time, by installing Ubuntu on your computer, you get a complete set of all applications necessary for work, and you can easily download everything that is missing from the standard package from the Internet. And there is no catch in this. You can use Ubuntu and all the software available on this system without any restrictions, absolutely free and on completely legal grounds. Moreover, you can even download the source code of all components of the system and make your own product based on it.

Ubuntu is supported and sponsored by Canonical, but the community makes a huge contribution to the development of this great OS - ordinary people, who are looking to improve the applications and tools they use. Perhaps someday you will want to help make Ubuntu is the best operating system and take part in the community.

About the resource

The purpose of this resource is to help beginners install Ubuntu on their computer and get comfortable with this system. I will say right away that all articles are written on the assumption that the reader has some knowledge of computers and will be able to distinguish a file from a folder. Although you don’t need any specific knowledge - just general computer literacy.

This resource is a beginner's guide, so if you haven't used Ubuntu before, I recommend that you read each article in order. If you already know something about Ubuntu and Linux in general, perhaps something will seem familiar to you. In this case, you can read the articles at your own discretion; use the menu on the right to navigate. By the way, if you don't feel comfortable reading the manual online, you can download a PDF version.

This guide is by no means exhaustive, but is intended to help you ease into the world of Ubuntu. If you have any questions, please contact the official Russian-language forum, they will always help you there, in addition there is community-created in Russian, in it you can search for the missing information.

A short summary

So what can you learn from this guide? Well, first of all, I’ll tell you how to install Ubuntu on your computer - the only operating system or next to Windows. Next, I'll touch a little on the user interface and basic system controls. And then I will try to consistently talk about all the necessary basics of using Ubuntu. By the way, many articles contain quite a lot of footnotes. They contain additional information or simply various comments on the main content. You may well skip them while reading. They are not necessary for understanding the main material of the manual, but are often useful as clarification of some specific questions that you may have.

I’ll say right away - there are practically no descriptions in the manual specific applications. There are a huge number of programs for Ubuntu to suit every taste and color. And I would really like not to recommend anything specific, but to show you how to find and install exactly what you personally like and suits best.

In general, the purpose of this manual is to teach the reader how to use all the main tools of the system with ease and effectively. I really hope that after reading it, you will be able to work calmly in Ubuntu and easily perform all the actions you need.

The guide describes the long term support version of Ubuntu - Ubuntu 10.04 LTS "Lucid Lynx".

Modern versions of Ubuntu are very different from "Lucid Lynx" user interface And pre-installed programs, so this guide is practically irrelevant for them.

For older versions there may also be slight differences from what is described in the articles, but general provisions will remain the same. However, I recommend that you always use latest version Ubuntu. In the first article I will tell you where you can get your copy of the distribution.

The idea of an introductory course on working with Linux came up with my colleagues quite a long time ago. Since 2011, I have been doing bioinformatics at the Laboratory of Algorithmic Biology of St. Petersburg Agrarian University RAS (and my partner wrote about what we are doing). It must be said right away that working as a bioinformatician without Linux is practically impossible, since most bioinformatics programs are created specifically for this operating system and work only on it.

Due to the fact that this is an area at the intersection of sciences, we constantly communicate with biologists. Biologists now have to work with very large amounts of data, so the ability to use Linux, the optimal operating system for such tasks, is becoming a necessary skill. In fact, it’s not just about the ability to handle Linux, but in general about computer literacy: what are the rules for working on the server, how to load and efficiently store data files, what programs to run to process them and how to do this, etc. - all those things that both simplify and speed up your work and greatly facilitate collaboration with colleagues. Despite the fact that you can figure out Linux on your own by reading smart books and websites, for people from a non-technical environment this often causes certain difficulties and many give up on initial stages mastering this OS (for example, getting acquainted with command line).

Based on our experience, my colleague Andrey Przhibelsky (@andrewprzh) and I initially intended to conduct several classes on computer literacy for biologists. And then this idea grew into a three-week open online course (MOOC) from the Institute of Bioinformatics in Russian, which was later narrowed down to an introduction to Linux as a starting point - since it turned out to be very, very difficult to fit everything into three weeks. The course has already started and has proven to be quite popular (at at the moment More than five thousand people have signed up for it), but the first deadline for assignments is November 24, so you can still join without losing points or just study the course in free mode (all materials will remain open).

If the community is interested, we will write a separate post about the preparation of the first online course in our life - it is not at all as simple and fast as it might seem at first glance.

But first I would like to dwell on the answers to the questions that we were asked most often. When preparing the course, we talked with the most different people and were faced with the fact that many did not understand at all where Linux was used, and had no idea that the system could be useful to them. So:

Why do you need to know how to use Linux now?

Many people don't notice, but Linux is already around us. All Android devices run on Linux, most servers on the Internet also use this operating system and there are many other examples. Of course, you can continue to use all these things without knowing Linux, but once you master the basics of this system, you can better understand the behavior of the things around you. In addition, when working with large amounts of data, Linux is simply necessary, because most complex calculations on huge amounts of data are performed on computers running Linux control. And this is not a random choice: most computing tasks are performed much faster on Linux than on Windows or Mac OS X.

How is Linux related to mastering other disciplines?

A huge share of scientific software, especially programs for processing big data (for example, in the field of bioinformatics) is developed specifically for Linux. This means that these applications simply cannot run on Windows or Mac OS X. So, if you do not know how to work in Linux, you are automatically deprived of the opportunity to use the latest scientific developments. In addition, by learning Linux, you will better understand how a computer works, because you will be able to give commands to it almost directly.

Why does this need a separate course?

Linux has a lot of features that are useful to know and, of course, be able to use them at the right time. Fortunately, modern Linux versions much more user-friendly than their counterparts 5-6 years ago. Now you don’t have to suffer for hours and even days and nights after installing the system to set up your Internet connection, printing on a printer, keyboard layouts, and so on. Anyone can start using Linux the same way they used Windows or Mac OS X after a minimal familiarity with this system, which will be calculated in minutes. However, the capabilities of Linux are much broader than “everyday” use. It is simply impossible to cover all the functionality of Linux even in a three-week course. However, we try to teach students how to use most of the basic features of Linux, and most importantly, we hope that those who complete the course will be able to successfully continue mastering Linux on their own.

What's interesting about Linux?

For us, Linux is like a very interesting book that you read and are happy to recommend to your friends and even feel envious that they still have time to get acquainted with this work. The only difference is that although we have been familiar with Linux for almost 10 years, we cannot say that we have “read” it in its entirety. You can always find something new for yourself in it, learn that many things that you are used to doing one way can be done completely differently - much easier and faster.

The more you get acquainted with Linux, the more interesting it becomes. And from the initial desire to “quickly turn off and reboot into the native and familiar Windows (Mac OS X)” you soon move into the state of “hmm, but this is not so bad” and a little later into “how could I even work in this Windows ?!” And while studying Linux, you can sometimes feel a little like a hacker or the hero of a movie about programmers =)

Our course consists of brief overview basic features of Linux, but for beginners this should be enough to get interested in Linux and dive a little into its philosophy. For example, we will spend most of the course working in the terminal, so beginners should get used to it and understand the advantages of this approach to computer control. For more advanced users, certain lessons of the course may be of interest - for example, about working with a remote server or programming in bash. .

How to check solutions to problems in a Linux course? Is this even possible?

The answer to this question was non-trivial - we thought for a long time about how to check tasks (for example, that the user installed Linux on his computer or edited a file in a certain editor) and how to come up with interesting tasks to really show real job with Linux. For some topics there were quite interesting approaches. For example, it was added specifically for the course new type tasks on the Stepic platform - connecting to a remote server (and opening a “terminal”) directly in the browser window - according to reviews from the first users, they liked it. Of course, the first time there were some rough edges, but overall, everything works quite well. A separate post from the developers will soon appear about the technical side of this issue. An example of such a task (to watch it live, you can sign up for the course):

It must be said that not all users perceived the tasks with humor. For example, we tested the skill of installing programs on Linux using the VLC program as an example. You had to install it on your system using one of the described methods, then open the help about the program, find the name of the first author and enter it into the verification form. We heard a lot of comments about this task :) And people made mistakes mainly in that they entered the first and last names, or just the first name, or part of the last name (and there it is double, with a hyphen!). In general, if you decide to take the course, then read the terms of the tasks more carefully and this will save a lot of time and nerves! True, there was a remark with the same author and to the point, it turned out that in older versions of VLC he is already in 14th place, so we added another author to the check, who is the first among the “old” list (and, by the way, the third in the “new” ).

Why is Linux so good?

The question is, of course, ambiguous. In my opinion one of key advantages What sets Linux apart from Windows or Mac OS X is that this operating system is developed by a huge community of programmers around the world, and not in two, albeit very large, companies (Microsoft and Apple). Source code this system is open and everyone can get acquainted with internal device Linux or participate in its development. Developers are developing it not only for user-buyers, but also for themselves, which is why such great progress in development and many of its other advantages are associated. As "bonuses" for ordinary users: Linux is free, there are practically no viruses on Linux (and virus developers themselves often work on Linux!), there are a huge number of versions of this system and everyone can choose the one they like!

And finally, I would like to talk about my first acquaintance with Linux in the work process (before that there was a separate course on studying, but I didn’t get much out of it, unfortunately). This incident impressed me so much that I still remember it. When I worked at the department at Polytechnic in my 3rd year, I needed to run one program for data processing. The program was written in C++, and we then worked in Windows XP. There were a lot of launches that needed to be done, they were pretty similar and usually took a couple of minutes. During this time, it was impossible to do anything else on the computer - it was completely frozen, so you could chat with other employees or just walk around the office. After about a couple of weeks of such launches, my supervisor advised me to try to do the same thing, but not in Windows, but in Linux. I then thought “well, what difference does it make?”, but I respected the manager so much, I recompiled the program and followed his advice. Imagine my surprise when I ran the same program on the same data and got the result (of course, exactly the same) in a few seconds! I didn’t even have time to get up from my chair, let alone take a walk...

Computer Science Center Blog

Due to the fact that this is an area at the intersection of sciences, we constantly communicate with biologists. Biologists now have to work with very large amounts of data, so the ability to use Linux, the optimal operating system for such tasks, is becoming a necessary skill. In fact, it’s not just about the ability to handle Linux, but about computer literacy in general: what are the rules for working on a server, how to load and effectively store data files, what programs to run to process them and how to do it, etc. . - all those things that both simplify and speed up your work and greatly facilitate collaboration with colleagues. Despite the fact that you can figure out Linux on your own by reading smart books and websites, for people from a non-technical environment this often causes certain difficulties and many give up at the initial stages of mastering this OS (for example, getting acquainted with the command line).

Based on our experience, my colleague Andrey Przhibelsky (@andrewprzh) and I initially intended to conduct several classes on computer literacy for biologists. And then this idea grew into a three-week open online course (MOOC) from the Institute of Bioinformatics in Russian, which was later narrowed down to an introduction to Linux as a starting point - since it turned out to be very, very difficult to fit everything into three weeks. The course has already started and turned out to be quite popular (more than five thousand people have signed up for it at the moment), but the first deadline for assignments is November 24, so you can still join without losing points or just study the course in free mode (all materials will remain open).

If the community is interested, we will write a separate post about the preparation of the first online course in our life - it is not at all as simple and fast as it might seem at first glance.

But first I would like to dwell on the answers to the questions that we were asked most often. While preparing the course, we talked to a variety of people and were faced with the fact that many did not understand at all where Linux was used, and had no idea that the system could be useful to them. So:

Why do you need to know how to use Linux now?

Many people don't notice, but Linux is already around us. All Android devices run Linux, most servers on the Internet also use this operating system, and there are many other examples. Of course, you can continue to use all these things without knowing Linux, but once you master the basics of this system, you can better understand the behavior of the things around you. In addition, when working with large amounts of data, Linux is simply necessary, because most complex calculations on huge amounts of data are performed on computers running Linux. And this is not a random choice: most computing tasks are performed much faster on Linux than on Windows or Mac OS X.

How is Linux related to mastering other disciplines?

Why does this need a separate course?

Linux has a lot of features that are useful to know and, of course, be able to use them at the right time. Fortunately, modern versions Linux is much more user friendly than their counterparts 5-6 years ago. Now you don’t have to suffer for hours and even days and nights after installing the system to set up your Internet connection, printing on a printer, keyboard layouts, and so on. Anyone can start using Linux the same way they used Windows or Mac OS X after a minimal familiarity with this system, which will be calculated in minutes. However, the capabilities of Linux are much broader than “everyday” use. It is simply impossible to cover all the functionality of Linux even in a three-week course. However, we try to teach students how to use most of the basic features of Linux, and most importantly, we hope that those who complete the course will be able to successfully continue mastering Linux on their own.

What's interesting about Linux?

Our course consists of a brief overview of the main features of Linux, but for new users this should be enough to get interested in Linux and dive a little into its philosophy. For example, we will spend most of the course working in the terminal, so beginners should get used to it and understand the advantages of this approach to computer control. For more advanced users, certain lessons of the course may be of interest - for example, about working with a remote server or programming in bash. .

How to check solutions to problems in a Linux course? Is this even possible?

The answer to this question was non-trivial - we thought for a long time about how to check tasks (for example, that the user installed Linux on his computer or edited a file in a certain editor) and how to come up with interesting tasks to really show real work with Linux. For some topics there were quite interesting approaches. For example, a new type of task was added specifically for the course on the Stepic platform - connecting to a remote server (and opening a “terminal”) directly in the browser window - according to the feedback from the first users, they liked it. Of course, the first time there were some rough edges, but overall, everything works quite well. A separate post from the developers will soon appear about the technical side of this issue. An example of such a task (to watch it live, you can sign up for the course):

Why is Linux so good?

The question is, of course, ambiguous. In my opinion, one of the key advantages of Linux over Windows or Mac OS X is that this operating system is developed by a huge community of programmers around the world, and not in two, albeit very large, companies (Microsoft and Apple). The source code of this system is open, and everyone can get acquainted with the internal structure of Linux or participate in its development. Developers are developing it not only for user-buyers, but also for themselves, which is why such great progress in development and many of its other advantages are associated. As “bonuses” for ordinary users: Linux is free, there are practically no viruses on Linux (and the virus developers themselves often work on Linux!), there are a huge number of versions of this system and everyone can choose the one they like!