The Linux kernel has been marked by constant growth throughout its history. Since the initial release of its source code in 1991, it has grown from a small number of C files under a license prohibiting commercial distribution to its state in 2009 of over 370 megabytes of source under the GNU General Public License.
Events leading to creation
The Unix operating system was conceived and implemented in the 1960s and first released in 1970. Its availability and portability caused it to be widely adopted, copied and modified by academic institutions and businesses. Its design became influential to authors of other systems.In 1983, Richard Stallman started the GNU project with the goal of creating a free UNIX-like operating system.As part of this work, he wrote the GNU General Public License (GPL). By the early 1990s there was almost enough available software to create a full operating system. However, the GNU kernel, called Hurd, failed to attract enough attention from developers leaving GNU incomplete.
Another free operating system project in the 1980s was the Berkeley Software Distribution (BSD). This was developed by UC Berkeley from the 6th edition of Unix from AT&T. Since BSD contained Unix code that AT&T owned, AT&T filed a lawsuit (USL v. BSDi) in the early 1990s against the University of California. This strongly limited the development and adoption of BSD.
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 features of the increasingly cheap and popular Intel 386 architecture for personal computers. These factors of a lack of a widely-adopted, free kernel provided the impetus for Torvalds's starting his project. He has stated that if either the GNU or 386BSD kernels were available at the time, he likely would not have written his own
The creation of Linux
In 1991, in Helsinki, Linus Torvalds began a project that later became the Linux kernel. It was initially a terminal emulator, which Torvalds used to access the large UNIX servers of the university. He wrote the program specifically for the hardware he was using and independent of an operating system because he wanted to use the functions of his new PC with an 80386 processor. Development was done on Minix using the GNU C compiler, which is still the main choice for compiling Linux today (although the code can be built with other compilers, such as the Intel C Compiler).
Linus Torvalds had wanted to call his invention Freax, a portmanteau of "freak", "free", and "x" (as an allusion to Unix). During the start of his work on the system, he stored the files under the name "Freax" for about half of a year. Torvalds had already considered the name "Linux,".
In order to facilitate development, the files were uploaded to the FTP server of the Helsinki University of Technology (HUT) in September 1991. Ari Lemmke, Torvald's coworker at the HUT who was responsible for the servers at the time, did not think that "Freax" was a good name. So, he named the project "Linux" on the server without consulting Torvalds.Later, however, Torvalds consented to "Linux".
Linux under the GNU GPL
Torvalds first published the Linux kernel under its own licence, which had a restriction on commercial activity.
The software to use with the kernel was software developed as part of the GNU project licensed under the GNU General Public License, a free software license. The first release of the Linux kernel, Linux 0.01, included a binary of GNU's Bash shell. In 1992, he suggested releasing the kernel under the GNU General Public License. He first announced this decision in the release notes of version 0.12. In the middle of December 1992 he published version 0.99 using the GNU GPL.Linux and GNU developers worked to integrate GNU components with Linux to make a fully-functional and free operating system.
GNU/Linux naming controversy
The designation "Linux" was initially used by Torvalds only for the Linux kernel. The kernel was, however, frequently used together with other software, especially that of the GNU project. This quickly became the most popular adoption of GNU software. In June 1994 in GNU's bulletin, Linux was referred to as a "free UNIX clone", and the Debian project began calling its product Debian GNU/Linux. In May 1996, Richard Stallman published the editor Emacs, in which the type of system was renamed from Linux to Lignux. This spelling was intended to refer specifically to the combination of GNU and Linux, but this was soon abandoned in favor of "GNU/Linux".
Torvalds announced in 1996 that there would be a mascot for Linux, a penguin. Larry Ewing provided the original draft of today's well known mascot based on this description. The name Tux was suggested by James Hughes as derivative of Torvalds' UniX.
There are many other well-known maintainers for the Linux kernel beside Torvalds such as Alan Cox and Marcelo Tosatti. Cox maintained version 2.2 of the kernel until it was discontinued at the end of 2003. Likewise, Tosatti maintained version 2.4 of the kernel until the middle of 2006. Andrew Morton steers the development and administration of the 2.6 kernel, which was released on 18 December 2003 in its first stable incarnation. Also the older branches are still constantly improved.
The largest part of the work on Linux is performed by the community: the thousands of programmers around the world that use Linux and send their suggested improvements to the maintainers. Various companies have also helped not only with the development of the Kernels, but also with the writing of the body of auxiliary software, which is distributed with Linux.
It is released both by organized projects such as Debian, and by projects connected directly with companies such as Fedora and openSUSE. The members of the respective projects meet at various conferences and fairs, in order to exchange ideas. One of the largest of these fairs is the LinuxTag in Germany (currently in Berlin), where about 10,000 people assemble annually, in order to discuss Linux and the projects associated with it.
Open Source Development Lab and Linux Foundation
The Open Source Development Lab (OSDL) was created in the year 2000, and is an independent nonprofit organization which pursues the goal of optimizing Linux for employment in data centers and in the carrier range. It served as sponsored working premises for Linus Torvalds and also for Andrew Morton (until the middle of 2006 when Morton transferred to Google). Torvalds works full-time on behalf the OSDL, developing the Linux Kernels.
Despite being open-source, a few companies profit from Linux. These companies, most of which are also members of the Open Source Development Lab, invest substantial resources into the advancement and development of Linux, in order to make it suited for various application areas. This includes hardware donations for driver developers, cash donations for people who develop Linux software, and the employment of Linux programmers at the company. Some examples are IBM and HP, which use Linux on their own servers, and Red Hat, which maintains its own distribution. Likewise Trolltech supports Linux by the development and GPL licensing of Qt, which makes the development of KDE possible, and by employing some of the X and KDE developers.
Competition from Microsoft
Although Torvalds has said that Microsoft's feeling threatened by Linux in the past was of no consequence to him, the Microsoft and Linux camps had a number of antagonistic interactions between 1997 and 2001. This became quite clear for the first time in 1998, when the first Halloween document was brought to light by Eric S. Raymond. This was a short essay by a Microsoft developer that sought to lay out the threats posed to Microsoft by free software and identified strategies to counter these perceived threats. However the Free Software Foundation issued a statement that Microsoft's production of proprietary software is bad for software users because it denies users "their rightful freedom."
Competition entered a new phase in the beginning of 2004, when Microsoft published results from customer case studies evaluating the use of Windows vs. Linux under the name “Get the Facts” on its own web page. Based on inquiries, research analysts, and some Microsoft sponsored investigations, the case studies claimed that enterprise use of Linux on servers compared unfavorably to the use of Windows in terms of reliability, security, and total cost of ownership.
In response, commercial Linux distributors produced their own studies, surveys and testimonials to counter Microsoft's campaign. Novell's web-based campaign at the end of 2004 was entitled “Unbending the truth” and sought to outline the advantages as well as dispelling the widely publicized legal liabilities of Linux deployment. Novell particularly referenced the Microsoft studies in many points. IBM also published a series of studies under the title “The Linux at IBM competitive advantage” to again parry Microsoft's campaign. Red Hat had a campaign called “Truth Happens” aimed at letting the performance of the product speak for itself, rather than advertising the product by studies
In the autumn of 2006, Novell and Microsoft announced an agreement to co-operate on software interoperability and patent protection.This included an agreement that customers of either Novell or Microsoft may not be sued by the other company for patent infringement. This patent protection was also expanded to non-free software developers. The last part was criticized because it only included non-commercial developers.
In July of 2009, Microsoft submitted 22,000 lines of source code to the Linux kernel under the GPLV2 license, which were subsequently accepted. (Although this has been referred to as "a historic move" and as a possible bellwether of an improvement in Microsoft's corporate attitudes toward Linux and open-source software, the decision is not altogether altruistic. According to the article cited, it promises to lead to significant competitive advantages for Microsoft.)
In 1994 and 1995, several people from different countries attempted to register the name "Linux" as a trademark. Thereupon requests for royalty payments were issued to several Linux companies, a step with which many developers and users of Linux did not agree. Linus Torvalds clamped down on these companies with help from Linux International and was granted the trademark to the name, which he transferred to Linux International. Protection of the trademark was later administered by a dedicated foundation, the non-profit Linux Mark Institute. In 2000, Linus Torvalds specified the basic rules for the assignment of the licenses. This means that anyone who offers a product or a service with the name Linux must possess a license for it, which can be attained through a unique purchase.
- 1983: Richard Stallman creates the GNU project with the goal of creating a free operating system.
- 1989: Richard Stallman writes the first version of the GNU General Public License.
- 1991: The Linux kernel is publicly announced on 25 August by the 21 year old Finnish student Linus Benedict Torvalds.
- 1992: The Linux kernel is relicensed under the GNU GPL. The first so called “Linux distributions” are created.
- 1993: Over 100 developers work on the Linux kernel. With their assistance the kernel is adapted to the GNU environment, which creates a large spectrum of application types for Linux. The oldest currently existing Linux distribution, Slackware, is released for the first time. Later in the same year, the Debian project is established. Today it is the largest community distribution.
- 1994: In March Torvalds judges all components of the kernel to be fully matured: he releases version 1.0 of Linux. The XFree86 project contributes a graphic user interface (GUI). In this year the companies Red Hat and SUSE publish version 1.0 of their Linux distributions.
- 1995: Linux is ported to the DEC Alpha and to the Sun SPARC. Over the following years it is ported to an ever greater number of platforms.
- 1996: Version 2.0 of the Linux kernel is released. The kernel can now serve several processors at the same time, and thereby becomes a serious alternative for many companies.
- 1998: Many major companies such as IBM, Compaq and Oracle announce their support for Linux. In addition a group of programmers begins developing the graphic user interface KDE.
- 1999: A group of developers begin work on the graphic environment GNOME, which should become a free replacement for KDE, which depended on the then proprietary Qt toolkit. During the year IBM announces an extensive project for the support of Linux.
- 2004: The XFree86 team splits up and joins with the existing X Window standards body to form the X.Org Foundation, which results in a substantially faster development of the X Window Server for Linux.