WIKIBOOKS
DISPONIBILI
?????????

ART
- Great Painters
BUSINESS&LAW
- Accounting
- Fundamentals of Law
- Marketing
- Shorthand
CARS
- Concept Cars
GAMES&SPORT
- Videogames
- The World of Sports

COMPUTER TECHNOLOGY
- Blogs
- Free Software
- Google
- My Computer

- PHP Language and Applications
- Wikipedia
- Windows Vista

EDUCATION
- Education
LITERATURE
- Masterpieces of English Literature
LINGUISTICS
- American English

- English Dictionaries
- The English Language

MEDICINE
- Medical Emergencies
- The Theory of Memory
MUSIC&DANCE
- The Beatles
- Dances
- Microphones
- Musical Notation
- Music Instruments
SCIENCE
- Batteries
- Nanotechnology
LIFESTYLE
- Cosmetics
- Diets
- Vegetarianism and Veganism
TRADITIONS
- Christmas Traditions
NATURE
- Animals

- Fruits And Vegetables



ARTICLES IN THE BOOK

  1. Adobe Reader
  2. Adware
  3. Altavista
  4. AOL
  5. Apple Macintosh
  6. Application software
  7. Arrow key
  8. Artificial Intelligence
  9. ASCII
  10. Assembly language
  11. Automatic translation
  12. Avatar
  13. Babylon
  14. Bandwidth
  15. Bit
  16. BitTorrent
  17. Black hat
  18. Blog
  19. Bluetooth
  20. Bulletin board system
  21. Byte
  22. Cache memory
  23. Celeron
  24. Central processing unit
  25. Chat room
  26. Client
  27. Command line interface
  28. Compiler
  29. Computer
  30. Computer bus
  31. Computer card
  32. Computer display
  33. Computer file
  34. Computer games
  35. Computer graphics
  36. Computer hardware
  37. Computer keyboard
  38. Computer networking
  39. Computer printer
  40. Computer program
  41. Computer programmer
  42. Computer science
  43. Computer security
  44. Computer software
  45. Computer storage
  46. Computer system
  47. Computer terminal
  48. Computer virus
  49. Computing
  50. Conference call
  51. Context menu
  52. Creative commons
  53. Creative Commons License
  54. Creative Technology
  55. Cursor
  56. Data
  57. Database
  58. Data storage device
  59. Debuggers
  60. Demo
  61. Desktop computer
  62. Digital divide
  63. Discussion groups
  64. DNS server
  65. Domain name
  66. DOS
  67. Download
  68. Download manager
  69. DVD-ROM
  70. DVD-RW
  71. E-mail
  72. E-mail spam
  73. File Transfer Protocol
  74. Firewall
  75. Firmware
  76. Flash memory
  77. Floppy disk drive
  78. GNU
  79. GNU General Public License
  80. GNU Project
  81. Google
  82. Google AdWords
  83. Google bomb
  84. Graphics
  85. Graphics card
  86. Hacker
  87. Hacker culture
  88. Hard disk
  89. High-level programming language
  90. Home computer
  91. HTML
  92. Hyperlink
  93. IBM
  94. Image processing
  95. Image scanner
  96. Instant messaging
  97. Instruction
  98. Intel
  99. Intel Core 2
  100. Interface
  101. Internet
  102. Internet bot
  103. Internet Explorer
  104. Internet protocols
  105. Internet service provider
  106. Interoperability
  107. IP addresses
  108. IPod
  109. Joystick
  110. JPEG
  111. Keyword
  112. Laptop computer
  113. Linux
  114. Linux kernel
  115. Liquid crystal display
  116. List of file formats
  117. List of Google products
  118. Local area network
  119. Logitech
  120. Machine language
  121. Mac OS X
  122. Macromedia Flash
  123. Mainframe computer
  124. Malware
  125. Media center
  126. Media player
  127. Megabyte
  128. Microsoft
  129. Microsoft Windows
  130. Microsoft Word
  131. Mirror site
  132. Modem
  133. Motherboard
  134. Mouse
  135. Mouse pad
  136. Mozilla Firefox
  137. Mp3
  138. MPEG
  139. MPEG-4
  140. Multimedia
  141. Musical Instrument Digital Interface
  142. Netscape
  143. Network card
  144. News ticker
  145. Office suite
  146. Online auction
  147. Online chat
  148. Open Directory Project
  149. Open source
  150. Open source software
  151. Opera
  152. Operating system
  153. Optical character recognition
  154. Optical disc
  155. output
  156. PageRank
  157. Password
  158. Pay-per-click
  159. PC speaker
  160. Peer-to-peer
  161. Pentium
  162. Peripheral
  163. Personal computer
  164. Personal digital assistant
  165. Phishing
  166. Pirated software
  167. Podcasting
  168. Pointing device
  169. POP3
  170. Programming language
  171. QuickTime
  172. Random access memory
  173. Routers
  174. Safari
  175. Scalability
  176. Scrollbar
  177. Scrolling
  178. Scroll wheel
  179. Search engine
  180. Security cracking
  181. Server
  182. Simple Mail Transfer Protocol
  183. Skype
  184. Social software
  185. Software bug
  186. Software cracker
  187. Software library
  188. Software utility
  189. Solaris Operating Environment
  190. Sound Blaster
  191. Soundcard
  192. Spam
  193. Spamdexing
  194. Spam in blogs
  195. Speech recognition
  196. Spoofing attack
  197. Spreadsheet
  198. Spyware
  199. Streaming media
  200. Supercomputer
  201. Tablet computer
  202. Telecommunications
  203. Text messaging
  204. Trackball
  205. Trojan horse
  206. TV card
  207. Unicode
  208. Uniform Resource Identifier
  209. Unix
  210. URL redirection
  211. USB flash drive
  212. USB port
  213. User interface
  214. Vlog
  215. Voice over IP
  216. Warez
  217. Wearable computer
  218. Web application
  219. Web banner
  220. Web browser
  221. Web crawler
  222. Web directories
  223. Web indexing
  224. Webmail
  225. Web page
  226. Website
  227. Wiki
  228. Wikipedia
  229. WIMP
  230. Windows CE
  231. Windows key
  232. Windows Media Player
  233. Windows Vista
  234. Word processor
  235. World Wide Web
  236. Worm
  237. XML
  238. X Window System
  239. Yahoo
  240. Zombie computer
 



MY COMPUTER
This article is from:
http://en.wikipedia.org/wiki/Linux

All text is available under the terms of the GNU Free Documentation License: http://en.wikipedia.org/wiki/Wikipedia:Text_of_the_GNU_Free_Documentation_License 

Linux

From Wikipedia, the free encyclopedia

 

Linux, or GNU/Linux, refers to any Unix-like computer operating system which uses the Linux kernel. It is one of the most prominent examples of open source development and free software as well as user generated software; its underlying source code is available for anyone to use, modify, and redistribute freely.

Initially developed and used primarily by individual enthusiasts on personal computers, Linux has since gained the support of corporations such as IBM, Sun Microsystems, Hewlett-Packard, and Novell, Inc., and has risen to prominence as an operating system for servers; eight of the ten most reliable internet hosting companies now run Linux on their web servers.[1]

A KDE desktop on the SUSE Linux distribution.
A KDE desktop on the SUSE Linux distribution.

Linux has been more widely ported to different computing platforms than any other operating system. It is used in devices ranging from supercomputers to mobile phones, and is gaining popularity in the personal computer market.[2]

History

Main article: History of Linux

Early

Linus Torvalds - creator of the Linux kernel.
Linus Torvalds - creator of the Linux kernel.

In 1983, Richard Stallman founded the GNU Project, with the goal of developing a complete Unix-like operating system composed entirely of free software. By the beginning of the 1990s, GNU had produced or collected most of the necessary components of this system — libraries, compilers, text editors, a Unix shell — except for the core component, the kernel. The GNU project began developing a kernel, the GNU Hurd, in 1990, based on the Mach microkernel, but the development of this Mach-based design proved difficult and proceeded slowly.

Meanwhile, in 1991, another kernel was begun as a hobby by Finnish university student Linus Torvalds while attending the University of Helsinki.[3] Torvalds originally used Minix on his own computer, a simplified Unix-like system written by Andrew Tanenbaum for teaching operating system design. However, Tanenbaum did not permit others to extend his operating system, leading Torvalds to create a replacement for Minix.

Originally, Torvalds called his kernel "Freax" for "free" and "freak" and with the often-used X in the names of Unix-like systems. The name "Linux" was coined by Ari Lemmke, who administered an FTP server belonging to the Finnish University Network; he invented the name Linux for the directory from which Torvalds' project was first available for download.[4]

A graphic history of Unix systems. Linux is a Unix-type system but its source code does not descend from the original Unix.
A graphic history of Unix systems. Linux is a Unix-type system but its source code does not descend from the original Unix.

At first a computer running Minix was necessary in order to configure and install Linux. Initial versions of Linux also required another operating system to be present in order to boot from a hard disk, but soon there were independent boot loaders such as LILO. The Linux system quickly surpassed Minix in functionality; Torvalds and other early Linux kernel developers adapted their work for the GNU components and user-space programs to create a complete, fully functional, and free (as in freedom) operating system.

Today, Torvalds continues to direct the development of the kernel, while other subsystems such as the GNU components continue to be developed separately. Other groups and companies combine and distribute these components with additional application software in the form of Linux distributions.

Linux and the GNU Project

Richard Stallman, founder of the GNU project for a free operating system.
Richard Stallman, founder of the GNU project for a free operating system.
Main article: GNU/Linux naming controversy

The goal of the GNU project is to produce a Unix-compatible operating system consisting entirely of free software, and all general-purpose Linux distributions rely on numerous GNU components. The Free Software Foundation views these Linux distributions as "variants" of the GNU system, and asks that such operating systems be referred to as GNU/Linux or a Linux-based GNU system. While some distributions make a point of using the combined form - notably Debian GNU/Linux - its use outside of the enthusiast community is limited, and Linus Torvalds has said that he finds calling Linux in general GNU/Linux "just ridiculous".[5] The distinction between the Linux kernel and distributions based on it plus the GNU system is a source of confusion to many newcomers, and the naming remains controversial.

SCO litigation

Main article: SCO-Linux controversies

In March 2003, the SCO Group 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. Additionally, SCO sent letters to a number of companies warning that their use of Linux without a license from SCO may be actionable, and claimed in the press that they would be suing individual Linux users. This controversy has involved lawsuits by SCO against DaimlerChrysler (dismissed in 2004), and AutoZone, and by Red Hat and others against SCO. Furthermore, whether SCO even owns the relevant Unix copyrights is currently disputed by Novell.

As per the Utah District Court ruling on July 3, 2006; 182 claims out of 294 claims made by SCO against IBM have been dismissed.[6]

SCO's claims have varied widely.

Portability

Main article: Linux (kernel)#Portability

The Linux kernel was originally designed only for Intel 80386 microprocessors, but now supports a wide variety of computer architectures. Linux is one of the most widely ported operating systems, running on a diverse range of systems from the hand-held ARM-based iPAQ to the mainframe IBM System z9. Specialized distributions exist for less mainstream architectures. The ELKS kernel fork can run on Intel 8086 or 286 16-bit microprocessors, while the ΅Clinux kernel may run on systems without a memory management unit. The kernel also runs on architectures that were not intended to use other than their original operating systems: this is the case of computers made by Apple Computer such as the iMac and PowerBook, Palm PDAs, Nintendo GameCube and Xbox. New architectures, like Playstation 3's Cell microprocessor also runs linux, like many atypical devices such as iPods, set-top boxes, network switches, DVR's and cell phones.

Copyright, licensing, and the Linux trademark

The Linux kernel and most GNU software are licensed under the GNU General Public License version 2. The GPL requires that all distributed source code modifications and derived works also be licensed under the GPL, and is sometimes referred to as a "share and share-alike" or "copyleft" license. In 1997, Linus Torvalds stated, "Making Linux GPL'd was definitely the best thing I ever did."[7] Other software may use other licenses; many libraries use the GNU Lesser General Public License (LGPL), a more permissive variant of the GPL, and the X Window System uses the MIT License.

After more than ten years, the Free Software Foundation announced that they would be upgrading the GPL to version 3, citing increasing concerns with Intellectual Property laws, especially Software Patents. Linus Torvalds has publicly stated he would not move the Linux kernel to GPL v.3. Torvalds opposes in particular certain Digital Rights Management exclusions in the GPL v3.

In the United States, the name Linux is a trademark[8] registered to Linus Torvalds. Initially, nobody registered it, but on August 15, 1994, William R. Della Croce, Jr. filed for the trademark Linux, and then demanded royalties from Linux distributors. In 1996, Torvalds and some affected organizations sued to have the trademark assigned to Torvalds, and in 1997 the case was settled.[9] The licensing of the trademark is now handled by the Linux Mark Institute. Torvalds has stated that he only trademarked the name to prevent someone else from using it, but was bound in 2005 by United States trademark law to take active measures to enforce the trademark. As a result, the LMI sent out a number of letters to distribution vendors requesting that a fee be paid for the use of the name, and a number of companies have complied.[10]

Pronunciation

In 1992, Torvalds explained how he pronounces the word Linux (IPA: /'lɪnʉks/)

An audio file of Torvalds saying "Hello, this is Linus Torvalds, and I pronounce Linux as Linux" can be found online.[29][30] Note that in English, "Linux" and "Minix" are usually pronounced with a short i (IPA: /ɪ/) sound that is different from Torvalds' Finland Swedish pronunciation of these words.

Development

More Than a Gigabuck: Estimating GNU/Linux's Size, a 2001 study of Red Hat Linux 7.1, found that this distribution contained 30 million source lines of code.[11] Using the Constructive Cost Model, the study estimated that this distribution required about eight thousand man-years of development time. According to the study, if all this software had been developed by conventional proprietary means, it would have cost about 1.08 billion dollars (year 2000 U.S. dollars) to develop in the United States. [11] This distribution contained over fifty-five million source lines of code, and the study estimated that it would have cost 1.9 billion dollars (year 2000 U.S. dollars) to develop by conventional means.

Distributions

For more details on this topic, see Linux distribution.

Linux is predominantly used as part of a Linux distribution (commonly called a "distro"). These are put together by individuals, loose-knit teams, commercial and volunteer organizations. They commonly include additional system and application software, an installer system to ease initial system setup, and integrated management of software installation and upgrading. Distributions are created for many different purposes, including computer architecture support, localization to a specific region or language, real-time applications, and embedded systems, and many deliberately include only free software. Currently, over three hundred distributions are actively developed, with about a dozen distributions being most popular for general-purpose use.[12]

A typical general-purpose distribution includes the Linux kernel, some GNU libraries and tools, command-line shells, the graphical X Window System and an accompanying desktop environment such as KDE or GNOME, together with thousands of application software packages, from office suites to compilers, text editors, and scientific tools.

Desktop usage

A GNOME desktop running from the GNOME LiveCD.
A GNOME desktop running from the GNOME LiveCD.
See also: Comparison of Windows and Linux

The high level of access granted to Linux's internals has led to Linux users traditionally tending to be more technologically oriented than users of Microsoft Windows and Mac OS. Linux and other free software projects have been frequently criticized for not going far enough to ensure ease of use. [13] This stereotype has been dispelled in recent years. Linux is now typically being used with a user interface that is very similar to those running on other operating systems. However, users may sometimes have to switch to alternative application software, and there are often fewer "known" software choices for certain types of software (as in the case of computer games) but there exist replacements for all general-purpose software, and general applications like spreadsheets, word processors, and browsers are available for Linux in profusion. Additionally, a growing number of proprietary software vendors are supporting Linux,[14] . In the meantime, developers have resorted to using compatibility layers such as Wine or NdisWrapper allowing some Microsoft Windows application software and drivers to be used on Linux without requiring the vendor to adapt them. This is aimed at piggybacking on Window's commercial success.

Linux's roots in the Unix operating system mean that in addition to graphical configuration tools and control panels available for many system settings and services, plain-text configuration files are still commonly used to configure the OS and can readily be made accessible (or not) to users, at the administrator's will.

The Berlin-based organization Relevantive concluded in 2003 that the usability of Linux for a set of desktop-related tasks was "nearly equal to Windows XP."[15] Since then, there have been numerous independent studies and articles which indicate that a modern Linux desktop using either GNOME or KDE is on par with Microsoft Windows, even in a business setting.[16]

Enterprise usage

Linux has historically been used mainly as a server operating system. Linux is the cornerstone of the "LAMP" server-software combination (Linux, Apache, MySQL, Perl/PHP/Python) which has achieved popularity among developers, and which is one of the more common platforms for website hosting.

Due to its low cost and its high configurability, Linux is often used in embedded systems such as television set-top boxes, mobile phones, and handheld devices. Linux has become a major competitor to the proprietary Symbian OS found in many mobile phones, and it is an alternative to the dominant Windows CE and Palm OS operating systems on handheld devices. The popular TiVo digital video recorder uses a customized version of Linux.[17] Several network firewall and router standalone products, including several from Linksys, use Linux internally, using its advanced firewalling and routing capabilities.

Linux is increasingly common as an operating system for supercomputers. Of the 500 systems, 376 (75.2%) ran Linux.

Market share and uptake

Further information: Linux adoption

According to the market research company IDC, 25% of servers and 2.8% of desktop computers ran Linux as of 2004.[18] Proponents and analysts attribute the success of Linux to its security, reliability,[19] low cost, and freedom from vendor lock-in.[20] The frictional cost of switching and lack of support for certain hardware and application programs designed for Microsoft Windows, especially games or uncommon business software, have been two factors that have initially inhibited fast adoption.

The Linux market is rapidly growing and the revenue of servers, desktops, and packaged software running Linux is expected to exceed $35.7 billion by 2008.[21] The actual installed user base may be higher than indicated by this figure, as most Linux distributions and applications are freely available and redistributable.

The paper Why Open Source Software / Free Software (OSS/FS)? Look at the Numbers![22] identifies many quantitative studies of open source software on topics including market share and reliability, with many studies specifically examining Linux.

Installation

The most common method of installing Linux on a personal computer is by booting from a CD-ROM that contains the installation program and installable software. Such a CD can be burned from a downloaded ISO image, purchased alone for a low price, obtained as part of a box set, or in a few cases shipped for free by request. A box set may also include manuals and additional proprietary software. Mini CD images allow Linux to be installed from a disk with a small form factor. Linux also offers a more convenient method of installation by allowing users to download CD image files ISO and then the user can use a CD/DVD burning software to create installation CD's/DVD's themselves.

As with servers, personal computers that come with Linux already installed are available from vendors including Hewlett-Packard and Dell, although generally only for their business desktop line.

Alternatives to traditional desktop installation include thin client installation and running directly from a Live CD. In a thin client installation, the operating system is loaded and run from a centralised machine over a network connection. In a Live CD setup, the computer boots the entire operating system from CD without first installing it on the computer's hard disk.

On embedded devices, Linux is typically held in the device's firmware and may or may not be consumer-accessible.

Programming on Linux

Most Linux distributions support a wide array of programming languages. Core system software such as libraries and basic utilities are usually written in C or C++. Enterprise software is often written in Java, Perl, or Python.

The GNU Compiler Collection (GCC) is the standard C compiler family for most Linux systems. Amongst others, GCC provides frontends for C, C++ and Java.

Most distributions also include support for Perl, Python and other dynamic languages. Less common, but still well-supported, are C# via the Mono project, Scheme, and Ruby.

There are a number of Integrated development environments available including MonoDevelop, KDevelop, Anjuta, NetBeans, and Eclipse while the traditional editors Emacs and Vim remain popular. [23]

The two main widget toolkits used for contemporary GUI programming are Qt and the Gimp Toolkit, known as GTK+. Both support a wide variety of languages.

As well as these free and open source options, there are proprietary compilers and tools available from a range of companies such as the Intel C Compiler, PathScale [24], Micro Focus COBOL,[25], Franz Inc[26], and the Portland Group.[27]

Support

Technical support is provided by commercial suppliers and by other Linux users, usually in online forums, IRC, newsgroups, and mailing lists. Linux User Groups have traditionally been organized to provide support for Linux in specific cities and regions.

The business model of commercial suppliers is generally dependent on charging for support, especially for business users. A number of companies offer a specialized business version of their distribution, which adds proprietary support packages and tools to administer higher numbers of installations or to simplify administrative tasks.


 

See also

 
  • List of Linux distributions
  • Comparison of Linux distributions
  • The Cathedral and the Bazaar
  • Total cost of ownership
  • Linux software

References

  1. ^ Rackspace Most Reliable Hoster in September. Netcraft (October 7, 2006). Retrieved on 2006-11-01.
  2. ^ Burke, Steven. "Red Hat looks to boost channel sales", CRN, 2006-03-20. Retrieved on 2006-04-01.
  3. ^ Torvalds, Linux. "What would you like to see most in minix?". Usenet: comp.os.minix. Retrieved 2006-09-09 from [1]
  4. ^ Torvalds, Linus. "How to pronounce "Linux"?". Usenet: comp.os.linux. Retrieved 2006-08-08 from [2]
  5. ^ Moore, J.T.S. (Produced, Written, and Directed). (2001). Revolution OS [DVD].
  6. ^ SCO Losing Linux Battle With IBM.
  7. ^ Linus Torvalds interview. Retrieved on 2006-05-08.
  8. ^ U.S. Reg No: 1916230. Retrieved on 2006-04-01.
  9. ^ Linux Journal, 2006-06-31, Linux Timeline.
  10. ^ Linus gets tough on Linux trademark.
  11. ^ a b Wheeler, David A (2002-07-29). More Than a Gigabuck: Estimating GNU/Linux's Size. Retrieved on 2006-05-11.
  12. ^ The LWN.net Linux Distribution List. Retrieved on 2006-05-19.
  13. ^ Blau, John. "PC World - Linux Earns User-Friendly Rating", PC World, 2003-08-04. Retrieved on 2005-12-17].
  14. ^ The Global Desktop Project, Building Technology and Communities. Retrieved on 2006-05-07.
  15. ^ Relevantive Linux usability study. Retrieved on 2006-04-03.
  16. ^ Dulaney, Emmett (June 2005). Desktop Linux: Ready for Prime Time?. Retrieved on 2006-06-19.
  17. ^ TiVo - GNU/Linux Source Code. Retrieved on 2006-12-12.
  18. ^ White, Dominic (2004-04-02). Microsoft eyes up a new kid on the block. The Daily Telegraph. Retrieved on 2006-09-09.
  19. ^ Why customers are flocking to Linux.
  20. ^ The rise and rise of Linux.
  21. ^ Linux To Ring Up $35 Billion By 2008. Retrieved on 2006-04-01.
  22. ^ Wheeler, David A. Why Open Source Software / Free Software (OSS/FS)? Look at the Numbers!. Retrieved on 2006-04-01.
  23. ^ Brockmeier, Joe. A survey of Linux Web development tools http://programming.linux.com/programming/05/10/03/1828224.shtml?tid=63&tid=47 Retrieved 16/12/2006
  24. ^ http://www.pathscale.com/ekopath.html
  25. ^ http://www.microfocus.com
  26. ^ http://www.franz.com/
  27. ^ http://www.pgroup.com/
  28. ^ Re: How to pronounce "Linux"?. Retrieved on 2006-04-01. Torvalds' explanation of how to pronounce Linux.
  29. ^ http://www.kernel.org/pub/linux/kernel/SillySounds/. Retrieved on 2006-12-25.
  30. ^ Howto pronouce Linux?. Retrieved on 2006-12-17.
  • Torvalds, Linus, and David Diamond. Just for Fun: The Story of an Accidental Revolutionary. Harper-Collins Business.
  • Moody, Glyn. Rebel Code: Linux and the Open Source Revolution. Perseus Publishing. ISBN 0-7139-9520-3.
  • Gedda, R (2004). Linux breaks desktop barrier in 2004: Torvalds. Retrieved on 2004-01-16.
  • Mackenzie, K (2004). Linux Torvalds Q&A. Retrieved on 2004-01-19.
  • Greene, Thomas C. Mandrake 8.1 easier than Win-XP. The Register. Retrieved on 2005-12-22.

External links

Find more information on Linux by searching Wikipedia's sister projects:
 

 Dictionary definitions from Wiktionary
 Textbooks from Wikibooks
 Quotations from Wikiquote
 Source texts from Wikisource
 Images and media from Commons
 News stories from Wikinews
 Learning resources from Wikiversity
 

  • Linux.org — contains comprehensive information and resources about Linux.
  • Kernel.org — Linux kernel website
  • The Linux Documentation Project — HOWTOs, FAQs and other guides.
  • Linux Online — distributions and FTP sites (sortable by categories).
  • DistroWatch.com — distribution information and announcements.

Retrieved from "http://en.wikipedia.org/wiki/Linux"