Open source

Open-source computer software is software whose source code is either in the public domain or, more commonly, is copyrighted by one or more persons/entities but licensed to all according to an open source license. Such a license grants permission to use and redistribute the software, as well as to modify its source code and distribute modified versions, with at most minor restrictions (such as a requirement to preserve the authors' name and copyright statement in the code). The term open source in common usage may also refer to any software with publicly available source code, regardless of its license, but this usage provokes strong disapproval from the open source community.

"Open source" and "Free software"

In the strict definition, the term "open source" is distinct from "free software," and it should only be applied to software that meets the terms of the Open Source Definition (see also the Free Software Foundation's Free software definition). The decision to adopt the term "open source" was based partly on the confusion caused by the dual meaning of the word "free"; the FSF intended the word to mean "free speech, not free beer," but nevertheless, free software came to be associated with zero cost, a problem which was exacerbated by the fact that a great deal of it is, in fact, free of charge. It was hoped that the usage of the newer term "open source" would eliminate such ambiguity, and would also be easier to "market" to business users (who might mistakenly associate "free software" with anti-commercialism). Since its introduction, however, the "open source" label has been criticized for fostering an ambiguity of a different kind: that of confusing it for mere availability of the source, rather than the freedom to use, modify, and redistribute it.

The Free Software Definition is slightly more restrictive than the Open Source Definition; as a consequence of this, free software is open source, but open source software may or may not be "free." In practice, the amount of software released under a license that meets the open source definition, but which the FSF does not regard as free software, is quite small. (One of the few examples is the Apple Public Source License, which is considered open source but not free because it does not allow private modified versions.) For instance, software distributed under both the GPL and BSD licenses are considered both free and open source (the original BSD License had terms legally incompatible with the GPL, but this practical issue is a separate issue from its free-ness). Confusion about the distinctions between free and open source software is the source of some misunderstanding, particularly in the mass media, where the two are often applied interchangeably.

The open source movement

The open source movement is a large movement of programmers and other computer users to give easy access to computer software. It grew out of the Free software movement, and the line between the two is somewhat blurry. Mostly, the Free software movement is based upon political and philosophical ideals (sometimes referred as hacker culture), while open source proponents tend to focus on rather pragmatic matters. Both groups assert that this more open style of licensing allows for a superior software development process, and therefore that pursuing it is in line with rational self-interest. Free software advocates, however, would argue that "freedom" is a paramount merit that one should prefer (or at least weigh heavily) even in cases where proprietary software has some superior technical features.

Proponents of the open source development methodology claim that it is superior in a number of ways to the closed source method. Stability, reliability, and security are frequently cited as reasons to support open source. One successful application of the open source model is the Linux operating system, which is renowned for its stability and security characteristics. Among the works that explore and justify open source development is a series of works by Eric S. Raymond which includes The Cathedral and the Bazaar and Homesteading the Noosphere.

Open source advocates point out that as of the early 2000s, at least 90 percent of computer programmers are employed not to produce software for direct sale, but rather to design and customize software for other purposes, such as in-house applications. According to advocates, this statistic implies that the value of software lies primarily in its usefulness to the developer or developing organization, rather than in its potential sale value, and that consequently there is no compelling economical reason to keep source code secret from competitors.

People

• Bruce Perens, Eric Raymond, Linus Torvalds (The creator of Linux), Paul Vixie, Alan Cox
• Richard Stallman is a central figure in the rival (but cooperative) free software movement, which has a significantly different philosophical basis; Stallman does not want his name associated with the term open source.

Projects and Organizations

• Debian, FreeBSD, Mozilla, NetBSD, OpenBSD, OpenOffice.org, Open Source Initiative, OSDN, Slackware

Companies Involved in Open Source Development

• Apple, Caldera, Hewlett-Packard, IBM, Red Hat, Sun Microsystems

Examples of Open Source Licenses

• BSD License, GNU General Public License, GNU Lesser General Public License, MIT License, QING Public License[?], Cypherpunks Anti-license Mozilla public licence[?] Academic Free License Open Software License

For a more extensive list, see Open source license.

Examples of Open Source Software

• GNU Emacs, TeX, VIM, Apache, XFree86, the GIMP, PHP, Zope, KDE, Gnome, Linux, Mozilla, OpenOffice.org

For a more extensive list, see Open source software.

See also open content for non-programming open source projects.

See also: Closed source, Proprietary software, Halloween documents, Open Cola, SourceForge, GNU Savannah, Open Law project, Gift economy,

External links

• EU-funded report on the use of open-source software (http://www.infonomics.nl/FLOSS/report/)
• Open Source HealthCare Alliance (http://www.oshca.org/)
• Open Sources: Voices from the Open Source Revolution (http://www.oreilly.com/catalog/opensources/book/toc) - an online book containing essays from prominent members of the open source community
• Open Source Initiative OSI (http://www.opensource.org/index.php) - a list of available licenses
• The Institutional Design of Open Source Programming: Implications for Addressing Complex Public Policy and Management Problems (http://www.firstmonday.org/issues/issue8_1/schweik/index)
• The Asian Open Source Center (http://www.asiaosc.org) - has a lot of information on open source in Asia, much of it stored in a Wiki similar to Wikipedia.