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History
See also: History of the Linux kernelThe Unix operating system was conceived and implemented in the 1960s and first released in 1970. Its wide availability and portability meant that it was widely adopted, copied and modified by academic institutions and businesses, with its design being influential on authors of other systems. One so-called Unix-like system was the GNU Project, started in 1984, had the goal of creating a POSIX-compatible operating system from entirely free software. In 1985, Richard Stallman created the Free Software Foundation and developed the GNU General Public License (GPLv1), in order to spread the software freely. Many of the programs required in an OS (such as libraries, compilers, text editors, a Unix shell, and a GUI) were developed by the early 1990s, so that most of the requirements for an operating system were complete, although low level elements such as device drivers, daemons, and the kernel were stalled and incomplete[9]. Linus Torvalds has said that "If the GNU kernel had been ready last spring, I'd not have bothered to even start my project" [10].
MINIX, a Unix-like system intended for academic use, was released by Andrew S. Tanenbaum in 1987. While source code for the system was available, modification and redistribution were restricted. In addition, MINIX's 16-bit design was not well adapted to the 32-bit design of the increasingly cheap and popular Intel 386 architecture for personal computers.
In 1991, Linus Torvalds began to work on a non-commercial replacement for MINIX while he was attending the University of Helsinki.[11] This eventually became the Linux kernel.
Linux was dependent on the Minix userspace at first. With code from the GNU system freely available, it was advantageous if this could be used with the fledgling OS. Code licensed under the GNU GPL can be used in other projects, so long as they also are released under the same or a compatible license. In order to make the Linux kernel compatible with the components from the GNU Project, Torvalds initiated a switch from his original license (which prohibited commercial redistribution) to the GNU GPL.[12] Linux and GNU developers worked to integrate GNU components with Linux to make a fully functional and free operating system.[9]
Today Linux is used in numerous domains, from embedded systems[13] to supercomputers,[14] and has secured a place in server installations with the popular LAMP application stack.[15] Torvalds continues to direct the development of the kernel. Stallman heads the Free Software Foundation, which in turn develops the GNU components. Finally, individuals and corporations develop third-party non-GNU components. These third-party components comprise a vast body of work and may include both kernel modules and user applications and libraries. Linux vendors combine and distribute the kernel, GNU components, and non-GNU components, with additional package management software in the form of Linux distributions.
Technorati ProfileApplications
Desktop
Although in specialized application domains such as desktop publishing and professional audio there may be a lack of commercial quality software, users migrating from Mac OS X and Windows can find equivalent applications for most tasks.[41]
Many free software titles that are popular on Windows are also available, such as Pidgin, Mozilla Firefox, Openoffice.org, and GIMP, amongst others. A growing amount of proprietary desktop software is also supported under Linux,[42] examples being Adobe Flash Player, Acrobat Reader, Nero Burning ROM, Opera, RealPlayer, and Skype. In the field of animation and visual effects, most high end software, such as AutoDesk Maya, Softimage XSI and Apple Shake are available both for Linux, Windows and/or MacOS X. Additionally, CrossOver is a commercial solution based on the open source WINE project that supports running Windows versions of Microsoft Office and Photoshop.
- See also: Linux gaming
Servers and supercomputers
Historically, Linux has mainly been used as a server operating system, and has risen to prominence in that area; Netcraft reported in September 2006 that eight of the ten most reliable internet hosting companies run Linux on their web servers.[43] This is due to its relative stability and long uptime, and the fact that desktop software with a graphical user interface is often unneeded. Enterprise and non-enterprise Linux distributions may be found running on servers. 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.
Linux is commonly used as an operating system for supercomputers. As of June 2007, out of the top 500 systems, 389 (77.8%) run Linux.[44] Embedded devices
Due to its low cost and ability to be easily modified, an embedded Linux is often used in embedded systems. Linux has become a major competitor to the proprietary Symbian OS found in many mobile phones — 16.7% of smartphones sold worldwide during 2006 were using Linux[45] — 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.[46] Several network firewall and router standalone products, including several from Linksys, use Linux internally, using its advanced firewall and routing capabilities. The Korg OASYS and the Yamaha Motif XS music workstations also run Linux.
Many quantitative studies of open source software focus on topics including market share and reliability, with numerous studies specifically examining Linux.[47] The Linux market is growing rapidly, and the revenue of servers, desktops, and packaged software running Linux is expected to exceed $35.7 billion by 2008.[48] According to market research company IDC, 25% of servers and 2.8% of desktop computers ran Linux as of 2004.[49]
The difficulty of measuring the exact number of deployments becomes apparent when looking at IDC's report for Q1 2007, which says that Linux now holds 12.7% of the overall server market.[50] This estimate was based on the number of Linux servers sold by various companies, but since Linux servers are inherently free this number says nothing about the actual market share of the operating system, just how much money companies are making from selling it.
It has been alleged that people regard Linux as suitable mostly for computer experts because mainstream computer magazine reporters cannot explain what Linux is in a meaningful way, as they lack real life experience using it.[51] Furthermore, the frictional cost of switching operating systems and lack of support for certain hardware and application programs designed for Microsoft Windows have been two factors that have inhibited adoption. However, as of early 2007, significant progress in hardware compatibility has been made, and it is becoming increasingly common for hardware to work “out of the box” with many Linux distributions. Proponents and analysts attribute the relative success of Linux to its security, reliability,[52] low cost, and freedom from vendor lock-in.[53]