Linux - what is it? "Linux" and "Windows": what are the differences. Linux is a multitasking and multi-user operating system for education, business, and individual programming. Linux belongs to the family of UNIX-like operating systems

What features, what are the pros and cons of Linux today, on which dozens of other operating systems(OS)? Why is Linux becoming more popular? We will try to find answers to these questions in this material.

Experts believe that the Linux kernel will only be necessary for system programmers and developers of various embedded systems. Therefore, here it is necessary to talk only about the GNU/Linux OS (GNU is a free UNIX-like OS), which will be of interest to a wide range of consumers.

Features of Linux OS

GNU/Linux was the first free UNIX-like OS in active use. Back in the 90s, the server software niche already massively included this system. Now GNU/Linux systems are also used on a very large number of Internet servers; they are a system for supercomputers. This proves both the vitality and the great weight of the free software movement.
Most of the applications of this OS are distributed under a copyleft license (GNU General Public License, GPL), which does not allow the creation of non-free (proprietary) software. But this factor, as experts think, does not in the least interfere with making a profit from free software.
The creation of components is carried out by a large number of companies and people around the world. This is also a big plus, according to experts.

Advantages of GNU/Linux

“Freedom” of this software. Compared to proprietary systems, the main advantage of GNU/Linux, as well as other free operating systems (such as Free and Net, or OpenBSD, or OpenIndiana) is precisely the fact that they are freely distributed.

Free distribution means that users can run and use OS data for any needs, study and modify the operation of operating systems, and also help others by distributing copies of OS data and their various modifications.

Users have full control above own computer and executable tasks, without doing only what the specific corporation, the creator of the OS, allowed them to do, for their own benefit. First of all, this means the absence of surveillance by states and corporations, the absence various restrictions, which are aimed at luring money out of the user’s pockets. Provided good level privacy and security.

Hardware support. Lots of drivers for devices, especially on home systems (where non-server components are quite cheap). According to experts, there is a possibility that a particular system, such as BSD or OpenIndiana, will not support any equipment.

Numerous GNU/Linux distributions are able to function on older computers much better than systems such as Windows or macOS, which very often may not work at all on such PCs.

Active user support. Over the decades of its existence, GNU/Linux has acquired its own circle of users and developers who are able to quickly provide assistance with tasks or problems that arise during the work of inexperienced users.

Pros of free operating systems for developers

Minuses

Sometimes GNU/Linux support can be quite expensive financially. The cost of training and support should always be kept in mind. Price system administrators who are well versed in GNU/Linux can be much higher, and this factor completely offsets the savings from purchased copies of any Microsoft Windows.

There are situations when free software is much more expensive for a company - and even the fact of losing control over its PC, the fact of slavery from another corporation, does not particularly interfere. But much more often it happens that open source software saves much more money, while having ethical advantages.

The second minus is not so much high performance, as was expected. Many times it can be observed that the network and disk subsystem FreeBSD can be much more productive than GNU/Linux on the same hardware– this is what experts believe. It is not without reason that such well-known companies as Netflix and WhatsApp use FreeBSD on their own servers.

The third drawback is that some of the modern technologies. We are talking, first of all, about the ZFS subsystems (this is the most advanced file system that guarantees data integrity), DTrace ( great tool, suitable for debugging and for monitoring everything that happens in the kernel and in the software), Containers/Zones (this is a virtualization system). They originated under a free license in the OpenSolaris system (now called OpenIndiana), then were implemented in a number of BSD systems, but are not yet present in high-quality form in GNU/Linux.

The use of a microkernel (as, for example, happens in the proprietary Apple macOS) will potentially greatly increase the reliability and security of the system itself, and the Linux kernel could have already been microkernel at the time of writing, but this did not happen.

When is the best time to use GNU/Linux?

If GNU/Linux is installed and used in a company, and the benefits of changing this OS to another, for example, FreeBSD, are not particularly expected.
If the software you plan to work with uses GNU/Linux-specific features (for example, OpenStack software that is incompatible with anything else), then, of course, it is better to use GNU/Linux. Because rewriting the software will be too expensive.
When you need to do the most simple tasks. For example, carry out fast loading, launch LibreOffice, edit a document, copy something to a flash drive, view something in an Internet browser.
Such OS will be an excellent option for those who cannot afford to use macOS and Windows, in which case a free free OS (including - a large number of GNU/Linux distributions) will be an excellent replacement for you.

5. If a company is under surveillance or works with confidential data, then it is necessary to start using the vast majority of free operating systems (and GNU/Linux). Means of surveillance or means of weakening cryptographic means Such operating systems are usually not built into them.

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Characteristic features of Linux as an OS.

multitasking: many programs are executed simultaneously;
multi-user mode: many users work simultaneously on the same machine;
protected processor mode (386 protected mode);
process memory protection; a program failure cannot cause the system to freeze;
economical loading: Linux reads from disk only those parts of the program that are actually used for execution;
dividing pages by record between instances of a running program. This means that processes that are instances of a program can use the same memory when executing. When such a process attempts to write to memory, the 4-kilobyte page being written to is copied to free place
. with page organization (i.e., not the entire inactive process is displaced from memory to disk, but only the required page);
virtual memory in separate disk partitions and/or file system files; virtual memory capacity up to 2 GB; changing the size of virtual memory during program execution;
shared memory of programs and disk cache: all free memory is used to buffer exchanges with the disk;
dynamic loaded shared libraries;
program dump for post-mortem analysis: allows you to analyze with a debugger not only a running program, but also a program that has terminated abnormally;
POSIX.1 certified, source compatible with System V and BSD standards;
via iBCS2-matched emulator compatibility with SCO, SVR3, SVR4 for downloadable programs, availability of the source code of all programs, including kernel texts , drivers, development tools and applications. These texts are freely distributed. Currently, some companies supply a number of commercial programs without source texts
, but everything that was free remains free; job management in;
POSIX standard
coprocessor emulation is in the kernel, so the application doesn't have to worry about coprocessor emulation. Of course, if a coprocessor is available, then it is used;
support for national alphabets and conventions, incl. for Russian language; the ability to add new ones;
multiple virtual consoles: several simultaneous independent ones on one display work sessions, switchable from the keyboard;
support for a number of common file systems (MINIX, Xenix, file
System V); the presence of its own advanced file system with a capacity of up to 4 Terabytes and with file names of up to 255 characters;;
transparent access to DOS partitions (or OS/2 FAT): the DOS partition looks like part of the Linux file system;
VFAT support (WNT, Windows 95);
a special file system UMSDOS, which allows you to install Linux in a file

DOS system

The so-called virtual multi-console makes it possible to organize the operation of several consoles on one display. The broadcast process starts on the first console. The key combination Alt-F2 goes to the second console. The broadcast continues, but the first console on the display screen is replaced new picture second console. In which, for example, a text editor is launched. The Alt-F3 combination goes to the third console, in which the debugger is launched, etc. Typically there are 8 consoles in the system, but up to 64 can be installed. You can switch to any console at any time.

A separate console can run both a text and graphics program.

On one of the free consoles you can run a windowed graphics system X Window System. Open a window on the screen and play DOOM. It is possible through a network with a partner. And in other windows - database, mail, editor, broadcast, etc.

Thus, many consoles are running at the same time, and on one of the consoles there are also many X Window System windows.

In addition, background processes are simultaneously running in the system, which do not display information on the display, but do their work, for example, transmitting data via a modem, printing on a printer, transmitting mail over the network, etc. Background process can be initiated by both the user and the OS itself in accordance with the prevailing conditions (there is mail to send, data to print, it is time to communicate via modem, etc.).

Linux provides physical parallelization of calculations on multiprocessor machines (up to 32 processors), but this is not directly related to the simultaneous execution of several programs. The operating system allows multiple tasks to be performed simultaneously on a single processor, switching the processor from task to task hundreds of times per second.

How multiple users work on the same machine.

The user gains access to the system as a result of registration. The system displays the login: prompt on the console, and the user responds by entering his username and password. After checking access rights, the system prompts you to enter commands to execute programs, accepts commands and executes them, for example:

\ ______________________________ / \ ________________________________ /

A common practice is for a user to log in to different virtual consoles under different names. For example, to perform administrative functions on console 1, the user is logged in as root, to run an application program as eugene on console 2, to run a game as games on console 3, etc. The point of this approach is that different “users” have different identities in the system - access rights to resources, initial settings, files, etc.

If a machine is connected to a network, then remote registration of a user from machine A to machine B is possible, even when these machines are located on different continents (the Internet provides communication between machines on a planetary scale). A user on machine A issues a command like

Telnet machine_B.company_B.city_B.country_B

and after a second or two he sees an invitation on the screen

Machine_B login:

enters his name and password and ends up on the current console in machine B (if the password has confirmed access rights). From another console it is possible to log into another machine or again into machine B.

While in machine B, the user can issue the command

Telnet machine_A.company_A.city_A.country_A

and register again in your own car A from car B. IN general case

Eugene.mplik.ru $ telnet elvis.ru 2345 Connected to elvis.ru. English-Russian, Russian-English dictionary.e or . - output.h - help tr>unix operating system; originally developed at Bell Laboratories for minicomputers of the PDP-11 series and widely used on computers of various classes and types. Features of UNIX: program portability between UNIX implementations on different computers; orientation towards an interactive mode of operation and use, first of all, by programmers for developing programs; openness to add extensions. tr>.e Connection closed by foreign host. eugene.mplik.ru $

In addition to the network connection, a machine may have dozens of terminals connected via serial ports. The terminal consists of a screen and a keyboard, i.e. a console where the user can log in as usual. Only in this case the console is not virtual, but is represented by a specialized separate device. The terminal can serve Personal Computer, for example, running under DOS PC 286, on which a program is executed that simulates the logic of the console (transparent input from the local keyboard to the Linux machine and transparent output to the local display of data from the Linux machine).

Network...___________________________... |

____|____ ____ | | | | display | Linux |---|____| with virtual | | /___/ consoles |---------|

|_________| ports /|\ / | \ / | \communication lines/ | \ ____ ____ ____ | | | | | | terminals |____| |___| |___|

/_/ /_/ /___/

Connecting terminals located at a distance of more than two tens of meters requires the inclusion of intermediate matching devices, for example, modems, on the line. At the same time, the modem can provide connection switching, i.e. Several different terminals can take turns calling the computer's modem and ensuring that different users are registered.

All of the above methods for registering users in the system work together. Thus, on one machine, tens or hundreds of users logged into the system via various communication channels can simultaneously perform thousands of tasks.

Those who are used to dealing with pirated programs, suffering from a lack of documentation, will encounter a completely opposite situation in Linux. The problem is not that there is little documentation in Linux, but that there is a lot of it, it comes in many forms and is available from . In order to navigate this wealth of choice, some effort will be required.

The documentation is written in English. There are fairly complete versions of the documentation in German and Japanese. Russian translation is available on the Internet Linux books Installation and Getting Started - LINUX INSTALLATION AND FIRST STEPS. A number of books on the Unix system published in Russian may be useful. Some publications on Unix exist in electronic form on Relcom servers.

There is a reference book on the POSIX standard in Russian: Belyakov M.I., Rabover Yu.I., Fridman A.L. Mobile operating system: Directory. - M.: Radio and Communications, 1991. - 208 p. It is difficult for the novice user, but useful for a programmer familiar with the conceptual foundations of Unix and open systems.

Descriptions in Russian of the Unix architecture, the principles of building a network based on the TCP/IP protocols and a number of related issues exist in the form of files on the servers of the Relcom network.

As for the original documentation on Linux, the following main, but not exhaustive, forms can be distinguished: books, HOWTOs, FAQs, INFOs, MAN operational manuals, descriptions of software packages. Books are distributed in printed and electronic form; other forms are usually electronic, i.e. presented in the form of files as part of Linux system distributions and software packages distributed via the Internet and on CDs.

Often the same electronic document is available in the form of several files of the same content, but in different formats, for example, ascii, postsscript, html. One format is suitable for browsing and searching for keywords on a text-based display screen, while other formats are suitable for print-quality printing on a laser printer or for viewing on a graphical screen.

In the comp.os.linux.answers group of the Usenet news network, the latest versions of some Linux documents are regularly published (at the same time they appear on Internet servers, from where they can be obtained in various ways, including by e-mail, for example, via [email protected]).

As an example, here is a list of (incomplete) HOWTOs:

Bootdisk HOWTO
CDROM HOWTO
Commercial HOWTO
Cyrillic HOWTO
DOSEMU HOWTO
Distribution HOWTO
Ethernet HOWTO
HOWTO Index
Hardware Compatibility HOWTO
INFO-SHEET
Installation HOWTO
Kernel HOWTO
Electronic Mail HOWTO
NET-2 HOWTO
News HOWTO
PCI HOWTO
PCMCIA HOWTO
Printing HOWTO
SCSI HOWTO
Serial HOWTO
Sound HOWTO
UMSDOS HOWTO
UPS HOWTO
UUCP HOWTO
XFree86 HOWTO

The difference between Linux and other operating systems with a free license.

There are a number of other operating systems that are licensed to allow free copying. Of these, the FreeBSD system is the most popular in Russia.

Working in Linux or FreeBSD is not difficult for an experienced specialist. But for a beginner Linux is simpler easier to learn and easier to use.

Unlike FreeBSD, which is historically descended from Unix codes, the Linux kernel is written from scratch.

Both OS are excellent quality systems. One is better in some ways than the other, and vice versa. Both systems are actively developing, so they can quickly and repeatedly change their leading role in any aspect.

Whatever choice you make - Linux or FreeBSD - in either case it will be a good choice.

Linux and FreeBSD differ greatly in their development concepts. Moreover, among operating systems, Linux is generally unique in its philosophy.

This is a system made by users for users.

Linux is not just a free system that anyone can copy without restrictions. It is a free, open development system, and anyone, whether a resident of Washington or Yekaterinburg, can become a co-author of Linux by making a contribution, no matter how big or small.

In the world Linux is more popular FreeBSD. By some estimates, in 1995 the number of Linux installations reached 10 million. A print magazine, Linux Journal, is published. Dozens for sale different versions Linux CDs. Hundreds of Linux archives are available through global networks. The outgoing traffic of the Linux archive on the sunsite.unc.edu server amounts to tens of gigabytes per day. Several hundred users work with this archive around the clock at any given time, and to serve other thousands of people who want it, dozens of mirror copies of the Linux archive from sunsite have been created.

Linux User Groups (user associations) are springing up like mushrooms in the USA, Europe, Japan, and Australia. International conferences on Linux are held regularly. November 30 - December 2, 1994, the Linux section at the 6th OSW (Open Systems World), an international conference on open systems, was held in Washington. Sections of Novell AppWare, Windows NT, Solaris, and SCO Unix were running simultaneously. Since then, Linux has been a recurring topic on international Unix forums. At Unix Expo 95, there was fantastic interest in Linux; it was impossible to crowd the stands with Linux - Red Hat, Caldera, DEC, Linux Journal.

Accordingly, there are more materials on Linux and they are more accessible. There is a wide selection of inexpensive Linux CDROMs (compact discs). Thousands of megabytes of excellent quality software can be purchased for a few tens of dollars.

Ministry of Agriculture of the Russian Federation

Federal State educational institution higher professional education

Perm State Agricultural Academy

named after academician D.N. Pryanishnikov"

Department of Computer Science

Specialty "Accounting, analysis and audit"

Test

in computer science

Completed by a correspondence student

Batueva A.N.

Checked by a senior teacher:

Kritchenko T.N.

Perm, 2008

1. Theoretical task. operating room Linux system

1.1 Features that Linux OS provides

1.2 Who might need Linux OS and why?

1.3 Characteristics Linux as an OS

1.4 What does simultaneous execution of several programs look like?

1.5 How multiple users work on the same machine

1.6 How fully documented is the Linux OS?

1.7 Difference between Linux and other operating systems with a free license

1.8 Software supported by Linux system

1.9 Working with the Internet

1.10 Which word processor can be used on Linux

2. Practical task

2.1 Task 1

2.2 Task 2

2.3 Task 3

1. Linux operating system

Linux is a modern POSIX-compliant and Unix-like operating system for personal computers and workstations.

It is a multi-user network operating system with a networked graphical window system called XWindowSystem. Linux OS supports open systems standards and Internet protocols and is compatible with Unix systems, DOS, MSWindows. All components of the system, including source code, are distributed with a license for free copying and installation for an unlimited number of users.

The Linux operating system is widely used on the IntelPC 386/486/Pentium/PentiumPro platforms and is gaining ground on a number of other platforms.

The development of the Linux OS was carried out by Linus Torvalds of the University of Helsinki and an innumerable large team of thousands of Internet users, employees of research centers, foundations, universities, etc.

1.1 Features that the OS provides Linux

· makes it possible to freely and legally have a modern OS for use both at work and at home;

· has high performance;

· works reliably, steadily, absolutely without freezes;

· not susceptible to viruses;

· allows you to fully use the capabilities of modern PCs, removing the limitations inherent in DOS and MSWindows on the use of machine memory and processor resources;

· effectively manages multitasking and priorities, background tasks(long settlement, transfer Email via modem, formatting a floppy disk, etc. etc.) do not interfere interactive work;

· allows you to easily integrate your computer into local and global networks, incl. on the Internet; works with networks based on Novell and MSWindows;

· allows you to execute application programs of other operating systems presented in download format - various versions of Unix, DOS and MSWindows;

· provides the use of a huge number of different software packages accumulated in the Unix world and freely distributed along with source codes;

· provides a rich set of development tools application programs any degree of complexity, including client-server class systems, object-oriented, with a multi-window text and/or graphical interface, suitable for working in both Linux and other operating systems;

· gives the user and especially the developer a wonderful training base in the form of rich documentation and source texts of all components, including the kernel of the OS itself;

· allows everyone to try their hand at development, organize communication and working together via the Internet with any of the Linux OS developers and make your contribution by becoming a co-author of the system.

1.2 Who might need an OS and why? Linux

In using Linux various reasons many categories of users may be interested. It is impossible to provide an exhaustive list. However, here are some examples. Linux is a full-fledged 32-bit (64-bit on the DECAXP platform) operating system that uses the computer to its full capacity. Linux turns the IBMPC personal computer into a real one workstation. At the price of a personal computer, which is significantly lower than the cost of a workstation.

The price benefit is very large, since in addition to saving on hardware, Linux software comes with a free license that allows free, unlimited copying of the system. Kernel, editors, translators, DBMS, network, graphical interfaces, games and a lot of other software amounting to thousands of megabytes - free and legal.

Winnings only on software can range from thousands to tens of thousands of dollars. For many users in Russia, a free license is the only opportunity to legally provide themselves with a full set of software.

For the pirate market, not paying for programs is common practice. However, in the case of Linux, not only will no one prosecute you for this, they will also provide you with complete documentation! Moreover, with the source codes of all programs! The pirates never dreamed of this.

Linux is of great interest to consumers and application system developers. Imagine a company consisting of several branches, geographically located in different areas of the city and even in different cities and countries. A database server operates at the head office, clients - workstations in branches - interact with the server through the network. Such a system is quickly, cheaply and conveniently done in Linux. Think about Linux resilience. This is where it comes in very handy!

Linux opens the door to the gigantic world of open systems in which great amount tools for solving a wide variety of problems.

1.3 Features Linux like OS

· multitasking: many programs are executed simultaneously;

· multi-user mode: many users work simultaneously on the same machine;

· protected processor mode (386 protectedmode);

Process memory protection; a program failure cannot cause the system to freeze;

· dividing pages by record between instances of the executing program. This means that processes that are instances of a program can use the same memory when executing. When such a process attempts to write to memory, the 4-kilobyte page being written to is copied to free space. This property increases performance and saves memory;

· virtual memory with a page organization (i.e., not the entire inactive process, but only the required page is displaced from memory to disk); virtual memory in separate disk partitions and/or file system files; virtual memory capacity up to 2 GB; changing the size of virtual memory during program execution;

shared program memory and disk cache: all free memory used to buffer disk exchanges;

· dynamic loaded shared libraries;

· certification according to the POSIX.1 standard, compatibility with SystemV and BSD standards at the source level;

· via iBCS2-matched emulator compatibility with SCO, SVR3, SVR4 for downloadable programs,

· job management in the POSIX standard;

· availability of the source text of all programs, including kernel texts, drivers, development tools and applications. These texts are freely distributed. Currently, some companies supply a number of commercial programs for Linux without source code, but everything that was free remains free;

· coprocessor emulation in the kernel, so the application does not have to worry about coprocessor emulation. Of course, if a coprocessor is present, it is not used;

· support for national alphabets and conventions, incl. for Russian language; the ability to add new ones;

· multiple virtual consoles: on one display there are several simultaneous independent work sessions switched from the keyboard;

· support for a number of common file systems (MINIX, Xenix, SystemV file systems); the presence of its own advanced file system with a capacity of up to 4 Terabytes and with file names of up to 255 characters;

· transparent access to DOS partitions (or OS/2 FAT): the DOS partition looks like part of the Linux file system; VFAT support (WNT, Windows 95);

· special file system UMSDOS, which allows you to install Linux in the DOS file system;

· access (read only) to the HPFS-2 OS/2 2.1 file system;

· support for everyone standard formats CDROM;

· TCP/IP network support, including ftp, telnet, NFS, etc.

1.4 What does simultaneous execution of several programs look like?

The so-called virtual multi-console makes it possible to organize the operation of several consoles on one display. The broadcast process starts on the first console. The key combination Alt-F2 goes to the second console. The broadcast continues, but the first console on the display screen is replaced with a new picture of the second console. In which, for example, a text editor is launched. The Alt-F3 combination goes to the third console, in which the debugger is launched, etc. Typically there are 8 consoles in the system, but up to 64 can be installed. You can switch to any console at any time.

A separate console can run both a text and graphics program.

On one of the free consoles you can run the XWindowSystem windowed graphic system. Open a window on the screen and play DOOM. It is possible through a network with a partner. And in other windows - database, mail, editor, broadcast, etc.

Thus, many consoles are running at the same time, and on one of the consoles there are also many XWindowSystem windows.

Hello dear readers. When using computers, tablets, smartphones, we rarely delve into what is under their shell, what “RAM” they run on, etc. If a simple Windows user and Apple's Mac OS is often heard of, few people have heard of the “dark” horse Linux. Let's correct this misunderstanding together.

Linux is the kernel of the operating system itself. A great many systems are based on this kernel: Mint, Debian, Ubuntu, Fedora, Gentoo, this is just a small part of the huge list of systems. They are called distributions, sometimes Linux. It is noteworthy that some Linuxes were created on the basis of other Linuxes. For example, Mint on Ubuntu, and Ubuntu, in turn, on Debian.

The distribution kits differ little in their interface from the same Mac OS and Windows . The only significant difference is in the source files, in the operating system code.

There's another one important feature: The Linux system interface can be completely changed, as can its user environment.

Linux systems themselves differ from each other in their purpose. Some are created for the highest user requirements: Elementary OS, Ubuntu, Fedora, Debian. Others differ in the principle of settings: Slackware, Gentoo, Arch. Linux systems have also been created, focused mainly on protection and security.

The main advantage of distribution kits is that the user personally installs the components he needs. As a result, the computer becomes fast.

Another important fact about Linux . Powerful Android was created on its core. Unlike PC, large percentage phones and tablets run on the Android platform.

History of Linux.

Among the many students who read this work, there was one Linus Torvalds, Finnish by birth. Using the Minix operating system, he identified many shortcomings in it. Torvalds set about improving Minix and in 1991 released a new kernel called Linux.

It must be taken into account that a kernel without its environment is useless. So, ironically, at the same time, Richard Stallman was creating the GNU system with programs, but without a kernel. As a result, the merger resulted in a GNU/Linux system with a funny penguin symbol.

In addition, Torvalds wrote the book " Just for fun" about the history of Linux.

Pros and cons of Linux

The undoubted advantage of Linux is its high security features and reliability. As a result, it powers the world’s super-powerful computers, defense systems, and large serious servers serving a huge number of users.

As for viruses, there are too few of them to seriously threaten the security of Linux, and the likelihood that a virus will be able to cope with the system at all is low.

An undoubted advantage is that you don’t have to pay for a Linux system, like for many distros. There are only a few paid ones, one of which is RHEL, and then it is required mainly in business firms.

As for the developers, they are not out of work; installing special services brings them material profits: clouds, music stores, etc. It follows from this that you should not be afraid of any viruses, Trojans, or cracks - another big plus in favor of Linux, because installation of programs occurs either through the “Application Center” or through the official website.

Office workers and everyone Microsoft users Office note - the usual Microsoft application is being replaced with LibreOffice, which works with tables and text.

The disadvantage of Linux is the incompatibility of many interesting programs Windows. For example, Photoshop, 3DS Max, AfterEffects. To download on Linux, say Photoshop, you need a lot support programs, and even then some features will not be supported. There is an alternative: for Photoshop – Gimp, for 3DS Max – Blender. It should be taken into account that the same Gimp does not have all the functions of Photoshop, but for beginners it can be quite justified.

Another disadvantage is the lack of cool high-end games. However, the developers are already working hard on this.

Another interesting thing about Linux is that if a problem arises, you solve it and forget about it forever, unlike Windows. The system is customized for the user and works without failure for many years.

Something about Ubuntu

Once the most popular distribution, it has now been replaced by Mint. The creators of Ubuntu are the Canonical company under the leadership of an entrepreneur from South Africa and part-time second Space tourist Mark Shuttleworth.

This system is very convenient, it adapts to the user and has several options: for school computers - Xubuntu, with LXDE - Lubuntu, etc.

Ubuntu uses the Unity interface, which has a Launcher launcher, a Dash search tool, with built-in Wikipedia, Google.

The main feature of Unity is the so-called. the global menu, it is hidden at the top, opens quickly when you hover the mouse cursor.

Ubuntu users always support each other and help newbies. The word "ubuntu" means "humanity".

You can also join this fun and friendly community. Find out many incredible facts and subscribe to our blog.

Multi-user system

Linux was originally designed as a multi-user system. At the same time, it was not a question of: what computer Linux can be used by several people in turn, but about a real multi-user system, when several people simultaneously run their applications on the same computer. Is this necessary if we're talking about about a desktop, personal machine? Now you can firmly say “yes”. First, settings and application-related data are maintained independently and carefully for each user, which is essential in the now widely used sharing to applications and data. Secondly, for each user, the settings of his desktop are saved independently, each time he completes the registration procedure, he receives a familiar working environment.

The main part of the Linux OS is usually called the kernel. The core includes the most Lower level operating system functions, such as: hardware control, launching device drivers, file system management, process creation, memory management and others basic functions. Linux kernel is very similar to the UNIX kernel. The Linux kernel has some features that are completely unique:

the core is built on a modular basis

Several kernels can be installed on one computer at once

Linux kernel development is centrally managed

The Linux kernel is not a monolithic entity; some of its parts can be loaded during operation; these parts are called modules. If some functions are not required at the moment, then the modules responsible for them are not loaded and do not occupy memory. One computer can have several kernels installed at once, but only one of them is running at any given time. This feature allows you to test new versions of the kernel, assemble a more suitable configuration, and at the same time be able to very easily return back to old version, which was guaranteed to work. The development of the Linux kernel is still supervised by the legendary Linus Torvalds. This means that each version of the kernel is one single object.

Application Interoperability

The Linux operating system is not nearly as highly integrated as the operating system Windows system. In fact, every distribution consists of a kernel and hundreds, if not thousands of individual software packages associated with that kernel. All programs were originally designed and are being designed to allow close interaction, otherwise the systems would not be able to work. But this does not mean that they should interact; there may not be integration between them. In some cases, this lack of mandatory low-level integration may seem like a disadvantage, but this quality gives higher-level software developers the freedom to choose low-level applications and the ability to replace them later. Since the Linux kernel and almost everything available applications are based on open standards, integration between them is easy, and they work together reliably.

User interface

Typically, the user communicates with the computer through a graphical monitor, mouse and keyboard. Almost all client computers are designed this way, although appearance desktop and functionality may vary. Under Linux manager The graphical session is just one of the applications; it is not part of the operating system. This means that, firstly, you can choose a desktop manager (the most common choice is KDE or GNOME) and, secondly, you can work without a graphical environment at all, in alphanumeric mode.

Interaction with external infrastructure

A desktop computer rarely works on its own; it must interact with the surrounding infrastructure. It needs to be connected to local network, in access to servers and other shared resources. Linux supports all possible network protocols required for such interaction. The most important point when connecting a computer to to the outside world is a security issue. The Linux kernel has a built-in firewall that protects your computer from unauthorized access from outside and provides safe work end users and data security.

Data storage method

The way data is stored in Linux is radically different from the way it is used in Windows. File structure in Linux it is represented by one tree, while Various types partitions, including partitions on remote devices, look the same. There are no letters assigned to drives. This approach allows, for example, to adhere to the same logical structure catalogs for all client machines. A significant difference in file handling is the existence of links in most file systems that Linux runs on. Essentially, links are pointers to files or entire directories. There are two types of links: hard links and symbolic links. A hard link is just another name associated with a file, while a symbolic link is a free-standing pointer. If a file is deleted, the symbolic link to it is not deleted, but begins to point to the void. If there is more than one hard link to a file, then deleting one name will not delete the file. In reality, it will be deleted only after the last hard link is deleted.

Other differences

There are other features that distinguish Linux from other operating systems for desktop computers. Let's look at the difference in working with virtual memory and the concept of run levels, unique to Linux. Each operating system works differently with virtual memory, sometimes it even depends on the version of the operating system. Feature of Linux is that virtual memory will not be used until it is possible to work in real RAM. Windows, for example, begins to move information from RAM to disk and in other cases, there is a practice of preventive swapping. In many cases, this approach leads to a decrease in the speed of operations. Linux also adopts a caching system, that is, storing recently used file information in RAM. As a result of this practice, a significant portion of the RAM is constantly used. In the event that additional RAM required by applications, the system simply reduces the caching area. The concept of runlevels is common to UNIX/Linux-like operating systems. The runlevel determines which system services will be started when bootstrap systems. Runlevels are numbered from 0 to 9. For example, runlevel 3 corresponds to loading all system services, except for graphic ones. At level 5 it also starts graphical environment. Level 1 corresponds to a single-user system boot mode, in which only one console is available and almost all services are disabled.