In a narrowest feel, the term Linux refers to the Linux kernel, but these are usually wont to describe entire Unix-like operating systems (also known as GNU/Linux) that are according to a Linux kernel combined by using libraries & information from either a GNU project and more sources. Virtually all broadly, the Linux distribution bundles large quantities of application software with the core models, & will bring further user-friendly installation & upgrades.

At first, Linux was primarily developed & utilized by single enthusiasts. Since so, Linux has gained a trend lines of major corporations like IBM, Hewlett-Packard, and Novell for use around servers and is gaining popularity in the desktop market. Advocator & analysts attribute this profits to its vendor independence, low numbers, security, & dependableness. Linux was originally developed for Intel 386 microprocessors and now supports altogether popular computer architectures (and many obscure ones). These are deployed around applications ranging from either embedded systems (such as mobile phones and personal video recorders) to personal computers to supercomputers.

History
Inside 1983, Richard Stallman founded the GNU project, which today will bring an essential section of virtually all Linux systems (look at likewise GNU/Linux, following). the goal of Wildebeest was to get a complete Unix-like operating system composed totally of loose software package. Per beginning of the 1990s, GNU experienced produced or even collected 100% of the necessary components of this models—libraries, compilers, text editors, a Unix-rather shell, and more software program—except for a last level, the kernel. A Wildebeest design began getting their have kernel, a Hurd, in 1990 (after an abandoned attempt known as Trix). Based on data from Thomas Bushnell, a initial Hurd designer, their early project was to adapt the BSD 4.4-Lite kernel &, around hindsight, "It is now perfectly obvious to me that this would have succeeded splendidly and the world would be a very different place today" [http://www.groklaw.net/article.php?story=20050727225542530]. Notwithstanding, due to a deficiency of cooperation from either the Berkeley programmers, Stallman decided instead to use a Mach microkernel, which subsequently proved unexpectedly hard, & a Hurd's development proceeded slowly.

Meanwhile, within 1991, another kernel—finally dubbed "Linux"—was begun as a hobby by Finnish university student Linus Torvalds while attending the University of Helsinki. Torvalds originally utilized Minix, a simplified Unix-rather body written by Andrew Tanenbaum for teaching operating system project. But, Tanenbaum did non permit others to extend his operating patterns, leading Torvalds to respond with the replacement for Minix. Linux began retired as a terminal emulator written in IA-32 assembler and C, which was compiled into binary form and booted from either the floppy disk so that it would run outside of any operating system. A terminal copycat was going deuce threads: a single for sending & one for getting characters from either a serial port. While Linus required to see & write files to disk, this project-switching terminal ape was extended by having an entire filesystem handler. Fallowing that, it step by step evolved into an entire operating patterns kernel designed as a foundation for POSIX-compliant systems. A foremost version of the Linux kernel (Cypher.01) was freed to the Internet on September 17th, 1991, with a 2nd version resulting shortly thenceforth around October [http://groups.google.com/groups?selm=1991Oct5.054106.4647%40klaava.Helsinki.FI]. Since so, hundreds to thousands of developers from in the area of the world use participated in the plan. Eric S. Raymond's essay The Cathedral and the Bazaar discusses the development model of the Linux kernel and similar software.

Per Cipher.01 release, Linus experienced implemented plenty POSIX supervisor call instruction to produce Linux process a GNU Bash shell; after this bootstrapping procedure, development accelerated rapidly. The heading Minix rules was originally necessary sequentially to configure, compile, & set up Linux. Initial versions of Linux besides compulsory an operating technique to exist as present sequentially in addition from either a protective disk, however before long there were independent bootloaders, the virtually all swell known existence lilo. the Linux rules quickly surpassed Minix around functionality; Torvalds & more early Linux kernel developers adapted their kernel to function by having a Wildebeest components & user-space computer program to produce a complete, fully functional, loose operating technique.

In todays world, Torvalds continues to direct a development of a kernel, when more subsystems like the Wildebeest components come developed severally. A project of producing an integrated formulas, which combines tons one basic components along sustaining graphic interfaces (like GNOME or KDE, which in turn come according to a X Window System) and application software, is now performed by Linux distribution vendors/organizations.

Tux the penguin is the logo and mascot of Linux (although there are other, less most common representations; watch OS-tan), based on an image created by Larry Ewing in 1996. A title "Linux" was coined, does'nt by Torvalds, however by Ari Lemmke. Lemmke was working for the Helsinki University of Technology (HUT), located in Espoo near Helsinki, as an administrator of ftp.funet.fi, a FTP server which belongs to a Finnish University & The food & drug administration Network (FUNET), which hwhen many organizations as its members, amongst the babies the HUT and the University of Helsinki. He was a a single to invent a title Linux for the directory from either which Torvalds' task was 1st available for download [http://liw.iki.fi/liw/texts/linux-anecdotes.html]. A title was in the future trademarked (see beneath).

Licensing

A Linux kernel, along by having several of a Wildebeest components, is licensed under the GNU General Public License (GPL). the GPL takes that everthing source code modifications & derived works besides exist as licensed under a GPL, & is occasionally known as a "share and share-alike" (or even copyleft) license. Within 1997, Linus Torvalds stated, "Making Linux GPL'd was definitely the best thing I ever did." [http://kde.sw.com.sg/food/linus.html] More subsystems utilise more licenses, although a lot of a two part a property of existence free/open-source; for instance, many libraries utilise the LGPL (a other-permissive variant of the GPL), and a X Window Patterns utilizes a permissive (non-copyleft) MIT License.

A Linux trademark (SN: 1916230) is owned by Linus Torvalds, registered for "Computer operating system software to facilitate computer use and operation." A licensing of the trademark is okay, handled per Linux Mark Institute (LMI). LMI has too sought to enforce a Linux trademark around countries differently a United states of america. Witharound September 2005, Intellectual Property Australia, a trademark regulator in Australia, rejected an application to trademark Linux.

Pronunciation

Linux is normally pronounced either to rhyme by owning minix . A number one pronunciation is considered further right, when a 2nd has turn into popular for sounding further natural around English. More variations come besides imaginable, however less oftentimes heard.

Within 1992, Torvalds explained [http://groups.google.com/groups?selm=1992Apr23.123216.22024%40klaava.Helsinki.FI&output=gplain] (IPA pronunciations added to quote inside braces):

An audio file of Torvalds locution "Hello, this is Linus Torvalds, and I pronounce Linux as /linəks/" likewise is [http://www.paul.sladen.org/pronunciation/]. Note that within English, "Linux" & "Minix" come unremarkably pronounced sustaining the short /I/ healthy that is different from either Torvalds's Finland-Swedish pronunciation of these words.

Understand too List of words of disputed pronunciation for a discussion of the various ways "Linux" is pronounced.

Linux and GNU/Linux

Because a Wildebeest libraries & software online, an essential a portion of 100% Linux distributions, stem from an extended-standing loose operating models plan that predates a Linux kernel, Richard Stallman and the Free Software Foundation ask that the conjunct technique (disregardless of distribution) exist as known as GNU/Linux or even the Linux-depending Wildebeest technique. Torvalds, a author of the Linux kernel, has said that he finds career Linux in the main GNU/Linux "just ridiculous." However, occasionally distributions wash utilize this title — notably Debian GNU/Linux — while virtually all humans just refer to the body when Linux. A distinction between Torvalds' kernel & entire Linux-depending systems that contain a kernel occurs as perennial source of confusion, & a appellative remains controversial.

Litigation

Inside March 2003, the SCO Group (SCO) filed a lawsuit against IBM claiming that IBM had contributed portions of SCO's copyrighted code to the Linux kernel in violation of IBM's license to use Unix. In addition, SCO sent letters to the total of corporations warning that their apply of Linux while forgoing the license from either SCO can become actionable, & claimed in the click that it would be suing single Linux users. This contestation has included cause by SCO against Novell, DaimlerChrysler (partially dismissed inside July, 2004), and AutoZone, and by Red Hat and others against SCO.

Up to now, there is no proof of SCO's claims of traced code inside Linux has been provided & SCO's claims stand varied widely. Two or three of Novell's release seem to demonstrate good problems using SCO's claims: [http://www.novell.com/news/press/archive/2003/06/pr03036.html 2003-May-15] Novell Statement in SCO Contract Amendment (practiced news for Linux users) [http://www.novell.com/news/press/archive/2003/05/pr03033.html 2003-May-28] Novell Challenges SCO Position, Reiterates Trend lines for Linux [http://www.novell.com/news/press/pressroom/news_brief/archive/2003/05/pr03022.html 2003-May-30] Novell statement re: SCO click conference allegations [http://www.novell.com/news/press/archive/2003/06/pr03036.html 2003-Jun-06] Novell Statement in SCO Contract Amendment [http://www.novell.com/news/press/pressroom/news_brief/archive/2003/11/pr03042.html 2003-Nov-18] Novell Statement around SCO claims on the non-compete clause in Novell-SCO contracts

A virtually all comprehensive coverage of this lawsuit is from Groklaw.

Distributions

Linux is preponderantly utilized when section of the Linux distribution (distro). Which are actually compiled by souls, loose-knit teams, & various professional organisation. It include extra technique package & application programs, when well as certain processes to set up these systems in the computer. Distributions come created for numbers of different purposes, including localization, architecture support, real-time applications, and embedded systems, and numerous deliberately include single free software. On top 450 distributions come available [http://lwn.net/Distributions/].

a average general-all-purpose distribution includes the Linux kernel, some Wildebeest libraries and tools, command-line shells, and hundreds to thousands of application computer software packages, from either office suites and the in writing X Window System to compilers, text editors, and scientific information. The kind of Linux distribution screenshots may be viewed [http://shots.osdir.com/ here].

Development efforts

''To the higher degree a Gigabuck: Estimating GNU/Linux's Size, the learn of Red Hat Linux 7.1, discovered that this particular distribution contained 30 million source lines of code (SLOC). A Linux kernel contained Ii.Four million lines of code, or even 8% of the aggregate. Using the Constructive Cost Model (COCOMO), the learn forecasted that this distribution called upon astir eight thousand human-years of development instance. Got a lot this software system been developed by conventional proprietary means, it would have numbers Unity.08 billion dollars (month 2000 dollars) to respond with in the United States. Slightly all over half of a code therein distribution was licensed under the GPL.

Within the late survey, Counting potatoes: a size of Debian Two.Two'', a equivalent analysis was performed for Debian GNU/Linux version 2.Two. This distribution contained terminated fifty-5 million source lines of code, & a survey approximated that it would use at times numbers I.9 billion dollars (season 2000 dollars) to evolve by conventional proprietary means.

Applications
It used to be that, the user required important cognition of computers sequentially to set up & configure Linux. Because of this, & because of existence attracted by access to the internals of the body, Linux users own traditionally tended to become supplementary technologically oriented than users of Microsoft Windows and Mac OS, often revelling in the tag of "hacker" or "geek."

This stereotype has been dispelled around recent years per increased user-friendliness & wide adoption of numerous Linux distributions. Linux has processed considerable profits around server & favorite-purpose markets, like image giving & Web services, & is okay, making inroads into a high volume desktop market.

Linux is the cornerstone of the and so-alleged LAMP server-software combination (Linux, Apache, MySQL, Perl/PHP/Python) that has achieved widespread popularity among Web developers, making it one of a usual platforms in the internet.

Linux is likewise typically utilized within embedded systems. Its moo dollars and cents makes it particularly utile inside set-top boxes and for hardware like a Simputer, a computer aimed principally at on line-income populations inside developing nations. Around mobile phones, Linux has become the most common choice to the Symbian OS software. Within handheld devices, it is an option to the Windows CE and Palm OS operating systems. A popular TiVo PVR also uses the custom version of Linux. The big total of network firewalls and routers, including several from either Linksys, use Linux internally, do you need its advanced firewalling & routing capabilities. Linux is progressively commons as an operating rules for supercomputers, most recently in 64-bit AMD Opterons in the Cray XD1. These are as well expanding into telecommunications equipment across efforts like Carrier Grade Linux.

Linux is quickly gaining popularity as a desktop operating models. Around desktop environments like KDE and GNOME, Linux may be utilized by using the interface that is similar thereto of Mac OS, Microsoft Windows, other desktop environments, & its traditional Unix-prefer command line interface. Graphical Linux computer software system is for well-nigh any locality & inside a bit of areas there is a greater quality & quantity of software available than for proprietary operating systems.

Usability and market share
It used to be that viewed as an operating technique just computer geeks could utilize, Linux distributions keep close at hand get user-friendly, with numbers of graphic interfaces & applications.

Its market part of desktops is chop-chop growing. Based on data from marketing research company IDC, around 2002, 25% of servers and Ii.8% of desktop computers were already running off Linux. Nevertheless, argued benefits of Linux, like moo cost, fewer security vulnerabilities, & want of vendor lock-in, have spurred the growing total of high-profile subjects of mass adoption of Linux by corporations and governments. A Linux market is among a fastest growing & is projected to exceed $35.7 billion by 2008 [http://www.techweb.com/wire/showArticle.jhtml?articleID=55800522].

Linux & sir thomas more loose computer software projects own been oft criticized for non running far plenty within terms of ensuring serviceability, & Linux has been typically considered more hard to apply than Windows or the Macintosh, although it is steadily improving. Applications running off in graphical desktop environments such as GNOME and KDE in Linux are very similar to people heading in more operating systems. When occasionally applications just can not become rerun, there unremarkably is the replacement that might. The growing total of proprietary computer softwcome trafficker are supporting Linux, & open source development for Linux is as well steadily increasing. In addition, proprietary computer software for more operating systems can be dog across compatibility shells, like Wine. A front yard of devices & services configuration is in which user case is virtually all varied. GUI configuration information & panel come available for numbers of technique settings & services, however redaction of plain-text configuration files is typically expected. On the command shell, many usableness hangups from either early Unix days generally remainside, like a difficulty in searching for occasionally commands, & a inability to undo many operations such as file deletion. Numerous older computer program using text user interfaces (TUI) have uncivilized inconsistencies between the children, however it maintain fast followings.

It used to too become gentler to call for even local technical indicator trend lines for Windows or Mac OS than for Linux inside a select few wharehouses. These are worth noting that an operating formulas's usability is subjective & contingent on the background and needs of its users. For instance, Gentoo Linux, a source-based distribution, is time-ingesting to set up, however may be other usable for advanced users than extra beginner-friendly distributions, like Mandriva.

Users may st& to switch application package, and there can be fewer alternatives, when in the outbreak of computer games. Equivalents of a select few specific software might not exist as available. Yet, general applications prefer spreadsheets, word processing system, & browsers come available for even Linux around profuseness, &, because of loose distribution, the user could buy what lawsuits him or her.

Virtually all distributions of Linux st& ii or supplementary means of computer software installation, & additional professional and prevent-user applications currently accompany an machine-driven installation program. Because of reluctance to vary & the fact that numbers of computers accompany Windows pre-installed, there has been a slow initial adoption of recently desktop operating systems. Linux is preceding that stage at present, by using numerous manufacturers installing Linux & many organizations by owning 5 or even even supplementary years case with Linux - since installation evolved to graphical user interfaces - or Unix, which has been as much as for decades. Linux is quickly gaining popularity when a desktop operating body as these come additional & more utilized within schools & work and more population are becoming acquainted it.

Trend lines sure enough fresh & obscure devices remains an issue. Though a few seller provide device drivers, many driver must become developed by volunteers fallowing a release of the product. Typically, this development takes reverse engineering of some sort, when certain manufacturers remain closemouthed & refuse to provide devices or even firmware specifications for their products. Deliberately non-personal devices drivers rather Winmodems and Winprinters have been a general condition.

There develop been conflicting studies of Linux's serviceableness & dollars and cents it used to be that. Microsoft-sponsored studies like people by IDC have argued that Linux had the higher total cost of ownership (TCO) than Windows. All the same, Relevantive, the notable Berlin-based organization specializing inside providing consultation to corporations on the serviceableness of software system & Web services, concluded that the serviceableness of Linux for a placed of desktop-related tasks is "equal to Windows XP." Since then, there use at times been many independent studies that indicate that the modern Linux desktop utilizing Gnome or even even KDE get on par using or superior to Microsoft Windows.

Linux distributions use at times been criticized for unpredictable development schedules, so making enterprise users less comfortable sustaining Linux than it will become by owning more systems (Marcinkowski, 2003). Nevertheless, a few observers claim that a intervals between Linux distribution releases come there is no worse, & typically better, than a project management "schedule slipping" that occurs sustaining more operating systems & with package in the main. A heavy total of options of Linux distributions can besides confuse users & computer software marketer.

A paper [http://www.dwheeler.com/oss_fs_why.html Why Open Source Software / Free Software (OSS/FS)? View a Cost!] identifies numerous quantitative studies of open source software system, in topics including market part & reliableness, by using numerous studies specifically examining Linux.

Installation

It used to be that, difficulty of installation was a barrier to wide adoption of Linux-depending systems, however the run has been mass produced more easygoing inside recent years. Numerous distributions come at least as easy to set up as a corresponding version of Windows. These are unneeded to file registration number & enter the children in the period of installation. As well, personal computers that come with Linux distributions already installed are readily available from either many vender, including big mainstream marketer such as Hewlett-Packard, Wal-Mart and Dell.

the usual method of installing Linux, supported by tons major distributions, is by booting from either a CD that contains the installation program & installable software system. Such the Video may be burned from either the downloaded ISO image, purchased alone for even the moo price, or could be found when a share of a pack placed that may as well include manuals & extra commercial software package.

A few distributions, like Debian, can be installed from either the little placed of floppy disks. When a basic technique is installed, other software package may be added by downloading it from either the Internet or even applying Videos.

More distributions, like Knoppix, can be rerun directly from either the "live CD" running entirely within RAM, rather than installing it to the hard drive. By using this, 1 boots from either a Video & may have Linux forgoing making any modification to the contents of the disc drive. Likewise, a bit of minimum distributions, like tomsrtbt, can be rerun directly from either a placed of floppy disks while forgoing looking for to vary the disk drive contents.

However an additional mode of installatiin of Linux is to set up on a mighty computer to utilise when a server & to have average less right machines (possibly forgoing disc drive, & getting less memory & slower CPUs) as clients on top the network. Clients may boot on top a network from either a server & display resolutions & pass reference to the server in which all the applications redo. a Linux Terminal Server occurs as la single machine to which numbers of clients may attach this way, therefore a single obtains the gain of installing Linux in numbers of machines for the numbers of installing in one. the clients may be average PCs using a additiin of the network bootloader on a cause or even network interface controller. Variations on this mode include applying local causes & computing power to rerun applications. A dollars and cents achieved by utilizing thinly clients may be invested around greater computing power or even storage on the server.

Numerous distributions besides trend lines booting above the network, and so an installatiin on the properly designed machine may be done remotely.

Anaconda, one of the other popular installers, is utilized by Red Hat, Fedora and other distributions to simplify a installation run. These are notable for its ability to automatically partition a hard drive using the Disk Druid utility.

Installation on an existing platform

Numerous distribution corporations currently come sparing there are no effort to provide users by owning advanced, convenient & specific installations. A few beginners (especially victims acquainted Microsoft Windows & Mac OS) might however sense that making a shift may be strong however numerous solutions keep close at hand been created to solve this condition.

A few let a user set up Linux in top of their todays technique. Assume WinLinux, for example. When downloading a installer (to a higher degree 100MB), a user potty set up Linux upright prefer any more Windows application. the software package will bring all the required features; these are a really Linux distribution. a difference is that these are non necessary for the user to leave Windows, since the Linux OS is installed to the Windows protective-disk partition. a Linux boot loader might boot a Linux technique while a PC is restarted & the user chooses in addition Linux. Similar approaches include coLinux.

Technology of virtual machines (such as Virtual PC or VMware) also enables Linux (or even any more OS) to exist as redo in Windows. A virtual machine software package might simulate an isolated environment onto which a Linux models is installed. When all about is done, a virtual machine may be booted even as whenever it were an independent computer.

Demonstration

the difficulty around demonstrating Linux is however a major obstacle, slowing its adoption as a portable computing platform. Linux User Groups or LUGS, still provide a primary face-to-face forum for demonstration of Linux. Commercial exhibitions provide Linux demonstrations to expected newly users, especially corporate vendee. Numerous commercial distributions come protective to set up, however by having function, allow soul to re-apply an old machine to watch what a Linux desktop is rather. A approach by Knoppix, which runs Linux remove of a Video forgoing disturbing the PC's disk drive, is probably a virtually all successful demonstration convienence up to now. [http://www.mepis.org/ MEPIS] as well diarrhethe off a Video rather Knoppix and they two can besides become installed onto the PC such as any more Linux distribution. A fastest approach is probably that of Workspot, which uses VNC to provide a loose Linux desktop demonstration low (available [http://www.workspot.com here]).

Configuration

Configuration of virtually all technique wide settings come stored within one directory known as /etc, when user-specific settings come stored inside hidden files in the user's residence directory. Two or three software online apply the configuration database instead of files.

There are the total of ways to vary these settings. A easiest way to wash this is by utilizing information provided by distributions like Debian's debconf, Mandriva's Control Center, or SUSE's YaST. Others, such as Linuxconf, Gnome System Tools, and Webmin, are not distribution-specific. There are too several command line utilities for configuring programs. Since 100% settings come stored inside average text files they can be configured by any text editor.

Running Windows applications

There are many ways to dog applications written for Windows in Linux, by owning variable levels of profits. A popular Wine software, along with a commercial derivatives Crossover Office and Transgaming's Cedega create an application compatibility layer by reimplementing the Windows API inside of Linux. Numbers of Windows software download redo within Linux at or so a equivalent speed utilizing these software download, & in a few lawsuits rerun sooner. Since these softwcome download are written forswearing apply of any Microsoft code, it don't expect the Windows license. Although compatibility is improving, within several shells week-by-week, applications that produce utilize of non-standard programming practices could own experience problems.

a similar option to heading Windows applications within Linux is to have the proprietary Win4Lin software, which converts Microsoft's version of the Windows API to run within Linux like than reimplementing it from either scratch. Since the legal copy of the Microsoft implementation of the Windows API is required, utilise of Win4Lin takes the copy of Windows.

The third option for running off Windows applications inside Linux is to utilise the virtual machine program and rerun a desired application along sustaining a entire virtual Windows operating models. VMware is the proprietary hardware virtualisation program that could start Windows therein way by having touching-right functionality, even so this approach potty carry a considerable speed & performance penalty. Good CPU emulators (such as QEMU or the slower counterpart Bochs) can be utilized, though to rerun the Windows program these copycat may besides demand the copy of Windows. Aside from either a performance difficulties, virtual machine approaches to running off Windows applications just can not integrate Windows software download into a Linux desktop, when it must instead redo within a virtual Windows desktop.

the 4th optiin is to begin the Windows applications on a Windows machine & apply VNC to view it on the Linux Desktop. This occurs as proficient guide if you develop of these application you can't migrate, & an old PC. It too works swell whenever numbers of humans (utilizing Linux) require occasional access to Windows applications, & could part one Windows PC for that purpose. This guide is particularly utile if you have the Windows lone item of devices, like a dongle, custom decoder card, or even occasionally USB hardware.

Programming on Linux
The total of compilers come available for Linux.

A GNU Compiler Collection (GCC) comes with a brobdingnagian majority of distributions. GCC supports C, C++ and Java among other languages.

There are as well a total of IDEs available for Linux, including the renowned Emacs. Occasionally of the virtually all popular come Anjuta, KDevelop, Glade (actually a user interface designer) & Eclipse.

Support

Technical indicator trend lines is provided by commercial provider & by more Linux users, commonly inside on the net forums, newsgroups & mailing lists. Linux User Groups (LUGs) all all over the world help several users, mostly locally, & typically as well hang on to "installfests" in which users might set up Linux by having the nearby hand.

A business model of commercial provider is usually depending on charging for trend lines, especially for business users. Third-person commercial trend lines is as well readily available.