Free and open-source software

"FLOSS", "FOSS", and "Free and Open-source" redirect here. For hardware, seeOpen-source hardware.For other uses of "Foss", seeFoss (disambiguation).For other uses of "Floss", seeFloss (disambiguation).

A screenshot of free and open-source software (FOSS):Fedora Linux 36running theKDE Plasma 5desktop environment,Firefox,Dolphin file manager,VLC media player,LibreOffice Writer,GIMP,andKCalc

Free and open-source software(FOSS) is software that is available under a license that grants the right to use, modify, and distribute the software, modified or not, to everyone free of charge. The public availability of the source code is, therefore, a necessary but not sufficient condition. FOSS is an inclusive umbrella term forfree softwareandopen-source software.FOSS is in contrast toproprietary software,where the software is under restrictivecopyrightorlicensingand the source code is hidden from the users.

FOSS maintains the software user's civil liberty rights via the "Four Essential Freedoms"of free software. Other benefits of using FOSS include decreased software costs, increasedsecurityagainstmalware,stability,privacy,opportunities for educational usage, and giving users more control over their own hardware. Free and open-source operating systems such asLinuxdistributions and descendants ofBSDare widely used today, powering millions ofservers,desktops,smartphones,and other devices.Free-software licensesandopen-source licensesare used bymany software packagestoday. Thefree software movementand theopen-source software movementareonline social movementsbehind widespread production, adoption and promotion of FOSS, with the former preferring to use the termsFLOSS,free or libre.

Overview

Further information:Alternative terms for free software

"Free and open-source software" (FOSS) is an umbrella term for software that is simultaneously considered bothfree softwareandopen-source software.The precise definition of the terms "free software" and "open-source software" applies them to any software distributed under terms that allow users to use, modify, and redistribute said software in any manner they see fit, without requiring that they pay the author(s) of the software aroyaltyor fee for engaging in the listed activities.

Although there is an almost complete overlap between free-software licenses and open-source-software licenses, there is a strong philosophical disagreement between the advocates of these two positions. The terminology of FOSS was created to be a neutral on these philosophical disagreements between theFree Software Foundation(FSF) andOpen Source Initiative(OSI) and have a single unified term that could refer to both concepts, although Richard Stallman argues that it fails to be neutral unlike the similar term; "Free/Libre and Open Source Software" (FLOSS).

Free software

Richard Stallman'sFree Software Definition,adopted by the FSF, definesfree softwareas a matter of liberty, not price,and that which upholds the Four Essential Freedoms. The earliest known publication of this definition of his free software definition was in the February 1986 editionof the FSF's now-discontinued GNU's Bulletin publication. The canonical source for the document is in the philosophy section of theGNU Projectwebsite. As of August 2017,it is published in 40 languages.

Four essential freedoms of Free Software

To meet the definition of "free software", the FSF requires the software's licensing respect the civil liberties / human rights of what the FSF calls the software user's "Four Essential Freedoms".

• The freedom to run the program as you wish, for any purpose (freedom 0).
• The freedom to study how the program works, and change it so it does your computing as you wish (freedom 1). Access to the source code is a precondition for this.
• The freedom to redistribute copies so you can help others (freedom 2).
• The freedom to distribute copies of your modified versions to others (freedom 3). By doing this, you can give the whole community a chance to benefit from your changes. Access to the source code is a precondition for this.

Open source

The Open Source Definitionis used by theOpen Source Initiative(OSI) to determine whether asoftwarelicense qualifies for the organization's insignia foropen-source software.The definition was based on theDebian Free Software Guidelines,written and adapted primarily byBruce Perens.Perens did not base his writing on the Four Essential Freedoms of free software from theFree Software Foundation,which were only later available on the web.Perens subsequently stated that he feltEric Raymond's promotion of open-source unfairly overshadowed the Free Software Foundation's efforts and reaffirmed his support for free software.In the following 2000s, he spoke about open source again.

History

Main article:History of free and open-source software

From the 1950s and on through the 1980s, it was common for computer users to have the source code for all programs they used, and the permission and ability to modify it for their own use.Software,including source code, was commonly shared by individuals who used computers, often aspublic-domain software(FOSS is not the same as public domain software, as public domain software does not contain copyrights). Most companies had a business model based onhardwaresales, and provided orbundled softwarewith hardware, free of charge.

By the late 1960s, the prevailing business model around software was changing. A growing and evolving software industry was competing with the hardware manufacturer's bundled software products; rather than funding software development from hardware revenue, these new companies were selling software directly. Leased machines required software support while providing no revenue for software, and some customers who were able to better meet their own needs did not want the costs of software bundled with hardware product costs. InUnited States vs.IBM,filed January 17, 1969, the government charged that bundled software was anticompetitive.While some software was still being provided without monetary cost and license restriction, there was a growing amount of software that was only at a monetary cost with restricted licensing. In the 1970s and early 1980s, some parts of thesoftware industrybegan using technical measures (such as distributing onlybinary copiesofcomputer programs) to preventcomputer usersfrom being able to usereverse engineeringtechniques to study and customize software they had paid for. In 1980, the copyright law was extended to computer programs in theUnited States—previously, computer programs could be considered ideas, procedures, methods, systems, and processes, which are not copyrightable.

Early on,closed-sourcesoftware was uncommon until the mid-1970s to the 1980s, when IBM implemented in 1983 an "object code only" policy, no longer distributing source code.

In 1983,Richard Stallman,longtime member of thehackercommunity at theMIT Artificial Intelligence Laboratory,announced theGNU project,saying that he had become frustrated with the effects of the change in culture of the computer industry and its users.Software development for theGNU operating systembegan in January 1984, and theFree Software Foundation(FSF) was founded in October 1985. An article outlining the project and its goals was published in March 1985 titled theGNU Manifesto.The manifesto included significant explanation of the GNU philosophy,Free Software Definitionand "copyleft"ideas. The FSF takes the position that the fundamental issueFree softwareaddresses is an ethical one—to ensure software users can exercise what it calls "The Four Essential Freedoms".

TheLinux kernel,created byLinus Torvalds,was released as freely modifiable source code in 1991. Initially, Linux was not released under either a Free software or an Open-source software license. However, with version 0.12 in February 1992, herelicensedthe project under theGNU General Public License.

FreeBSDandNetBSD(both derived from386BSD) were released as Free software when theUSL v. BSDilawsuit was settled out of court in 1993.OpenBSDforkedfrom NetBSD in 1995. Also in 1995, TheApache HTTP Server,commonly referred to as Apache, was released under theApache License 1.0.

In 1997,Eric RaymondpublishedThe Cathedral and the Bazaar,a reflective analysis of the hacker community and Free software principles. The paper received significant attention in early 1998, and was one factor in motivatingNetscape Communications Corporationto release their popularNetscape CommunicatorInternet suite asFree software.This code is today better known asMozilla FirefoxandThunderbird.

Netscape's act prompted Raymond and others to look into how to bring the FSF's Free software ideas and perceived benefits to the commercial software industry. They concluded that FSF's social activism was not appealing to companies like Netscape, and looked for a way to rebrand the Free software movement to emphasize the business potential of sharing and collaborating on software source code. The new name they chose was "Open-source", and quicklyBruce Perens,publisherTim O'Reilly,Linus Torvalds,and others signed on to the rebranding. TheOpen Source Initiativewas founded in February 1998 to encourage the use of the new term and evangelize open-source principles.

While the Open Source Initiative sought to encourage the use of the new term and evangelize the principles it adhered to, commercial software vendors found themselves increasingly threatened by the concept of freely distributed software and universal access to an application'ssource code.AMicrosoftexecutive publicly stated in 2001 that "Open-source is an intellectual property destroyer. I can't imagine something that could be worse than this for the software business and the intellectual-property business."Companies have indeed faced copyright infringement issues when embracing FOSS.For many years FOSS played a niche role outside of the mainstream of private software development. However the success of FOSS Operating Systems such as Linux, BSD and the companies based on FOSS such asRed Hat,has changed the software industry's attitude and there has been a dramatic shift in the corporate philosophy concerning its development.

Usage

See also:Linux adoption,Free software § Adoption,andOpen-source software § Adoption

Benefits over proprietary software

Personal control, customizability and freedom

See also:Vendor lock-in

Users of FOSS benefit from theFour Essential Freedomsto make unrestricted use of, and to study, copy, modify, and redistribute such software with or without modification. If they would like to change the functionality of software they can bring about changes to the code and, if they wish, distribute such modified versions of the software or often − depending on the software'sdecision making modeland its other users − even push or request such changes to be made via updates to the original software.

Privacy and security

See also:Open-source software security,Surveillance capitalism,Global surveillance disclosures (2013–present),andSoftware update system

Manufacturers of proprietary, closed-source software are sometimes pressured to building inbackdoorsor other covert, undesired features into their software.Instead of having to trust software vendors, users of FOSS can inspect and verify the source code themselves and can put trust on a community of volunteers and users.As proprietary code is typically hidden from public view, only the vendors themselves and hackers may be aware of anyvulnerabilitiesin themwhile FOSS involves as many people as possible for exposing bugs quickly.

Low costs or no costs

FOSS is often free of charge although donations are often encouraged. This also allows users to better test and compare software.

Quality, collaboration and efficiency

See also:§ Bugs and missing features

FOSS allows for better collaboration among various parties and individuals with the goal of developing the most efficient software for its users or use-cases while proprietary software is typicallymeant to generate profits.Furthermore, in many cases more organizations and individuals contribute to such projects than to proprietary software.It has been shown that technical superiority is typically the primary reason why companies choose open source software.

Drawbacks compared to proprietary software

Security and user-support

See also:Common good,Public participation,andProactive cyber defence § Measures

According toLinus's lawthe more people who can see and test a set of code, the more likely any flaws will be caught and fixed quickly. However, this does not guarantee a high level of participation. Having a grouping of full-time professionals behind a commercial product can in some cases be superior to FOSS.

Furthermore, publicized source code might make it easier for hackers to find vulnerabilities in it and write exploits. This however assumes that such malicious hackers are more effective thanwhite hat hackerswhichresponsibly discloseor help fix the vulnerabilities, that no code leaks orexfiltrationsoccur and thatreverse engineeringof proprietary code is a hindrance of significance for malicious hackers.

Hardware and software compatibility

Further information:Software incompatibilityandSystem requirements

Sometimes, FOSS is not compatible with proprietary hardware or specific software. This is often due to manufacturers obstructing FOSS such as by not disclosing theinterfacesor other specifications needed for members of the FOSS movement to writedriversfor their hardware - for instance as they wish customers to run only their own proprietary software or as they might benefit from partnerships.

Bugs and missing features

See also:§ Quality, collaboration and efficiency

While FOSS can be superior to proprietary equivalents in terms of software features and stability, in many cases it has more unfixed bugs and missing features when compared to similar commercial software.This varies per case, and usually depends on the level of interest in a particular project. However, unlike close-sourced software, improvements can be made by anyone who has the motivation, time and skill to do so.

A common obstacle in FOSS development is the lack of access to some common official standards, due to costlyroyaltiesor requirednon-disclosure agreements(e.g., for theDVD-Videoformat).

Less guarantee of development

There is often less certainty of FOSS projects gaining the required resources and participation for continued development than commercial software backed by companies.However, companies also often abolish projects for being unprofitable, yet large companies may rely on, and hence co-develop, open source software.On the other hand, if the vendor of proprietary software ceases development, there are no alternatives; whereas with FOSS, any user who needs it still has the right, and the source-code, to continue to develop it themself, or pay a 3rd party to do so.

Missing applications

As the FOSS operating system distributions ofLinuxhas a lowermarket shareof end users there are also fewer applications available.

Adoption by governments

Main article:Adoption of free and open-source software by public institutions

See also:Sovereignty,National security,Computer emergency response team,andGlobal public good

Country	Description
Brazil	In 2006, theBrazilian governmenthas simultaneously encouraged the distribution of cheap computers running Linux throughout its poorer communities by subsidizing their purchase with tax breaks.
Ecuador	In April 2008,Ecuadorpassed a similar law, Decree 1014, designed to migrate the public sector to Libre Software.
France	In March 2009, theFrench Gendarmerie Nationaleannounced it will totally switch toUbuntuby 2015. The Gendarmerie began its transition to open source software in 2005 when it replaced Microsoft Office with OpenOffice.org across the entire organization.In September 2012, the French Prime Minister laid down a set of action-oriented recommendations about using open-source in the French public administration.These recommendations are published in a document based on the works of an inter-ministerial group of experts.This document promotes some orientations like establishing an actual convergence on open-source stubs, activating a network of expertise about converging stubs, improving the support of open-source software, contributing to selected stubs, following the big communities, spreading alternatives to the main commercial solutions, tracing the use of open-source and its effects, developing the culture of use of the open-source licenses in the developments of public information systems. One of the aim of this experts groups is also to establish lists of recommended open-source software to use in the French public administration.
Germany	In the GermanCity of Munich,conversion of 15,000 PCs and laptops from Microsoft Windows-based operating systems to aDebian-based Linux environment calledLiMuxspanned the ten years of 2003 to 2013. After successful completion of the project, more than 80% of all computers were running Linux.On November 13, 2017, The Register reported that Munich was planning to revert to Windows 10 by 2020.But in 2020, Munich decided to shift back from Microsoft to Linux again.In 2022 Germany launchedOpen CoDE,its own FOSS repository and forum.
India	The Government ofKerala,India, announced its official support for free and open-source software in its State IT Policy of 2001,which was formulated after the first-ever Free software conference in India,Freedom First!,held in July 2001 in Trivandrum, the capital of Kerala. In 2009, Government of Kerala started the International Centre for Free and Open Source Software (ICFOSS).In March 2015 the Indian government announced a policy on adoption of FOSS.
Italy	The Italian military is transitioning to LibreOffice and theOpenDocumentFormat (ODF). LibreItalia Association announced on September 15, 2015, that the Ministry of Defence would over the next year-and-a-half install this suite of office productivity tools on some 150,000 PC workstations, making it Europe's second-largest LibreOffice implementation.By June 23, 2016, 6,000 stations have been migrated.E-learning military platform.
Jordan	In January 2010, theGovernment of Jordanannounced a partnership with Ingres Corporation (now namedActian), an open-source database-management company based in the United States, to promote open-source software use, starting with university systems in Jordan.
Malaysia	Malaysia launched the "Malaysian Public Sector Open Source Software Program", saving millions on proprietary software licenses until 2008.
Peru	In 2005, theGovernment of Peruvoted to adopt open source across all its bodies.The 2002 response to Microsoft's critique is available online. In the preamble to the bill, the Peruvian government stressed that the choice was made to ensure that key pillars ofdemocracywere safeguarded: "The basic principles which inspire the Bill are linked to the basic guarantees of a state of law."
Uganda	In September 2014, the Uganda National Information Technology Authority (NITA-U) announced a call for feedback on an Open Source Strategy & Policyat a workshop in conjunction with the ICT Association of Uganda (ICTAU).
United States	In February 2009, theWhite Housemoved its website to Linux servers usingDrupalfor content management.In August 2016, theUnited States governmentannounced a new federalsource codepolicy which mandates that at least 20% of custom source code developed by or for any agency of the federal government be released asopen-source software(OSS).In addition, the policy requires that all source code be shared between agencies. The public release is under a three-year pilot program and agencies are obliged to collect data on this pilot to gauge its performance. The overall policy aims to reduce duplication, avoid vendor 'lock-in', and stimulate collaborative development. A new websitecode.govprovides "an online collection of tools, best practices, and schemas to help agencies implement this policy", the policy announcement stated. It also provides the "primary discoverability portal for custom-developed software intended both for Government-wide reuse and for release as OSS".As yet unspecifiedOSS licenseswill be added to the code.
Venezuela	In 2004, a law inVenezuela(Decree 3390) went into effect, mandating a two-year transition to open source in all public agencies. As of June 2009,the transition was still under way.

Adoption by supranational unions and international organizations

European Union

"We migrated key functions from Windows to Linux because we needed an operating system that was stable and reliable -- one that would give us in-house control. So if we needed to patch, adjust, or adapt, we could."

Official statement of theUnited Space Alliance,which manages the computer systems for theInternational Space Station(ISS), regarding why they chose to switch from Windows to Linux on the ISS.

In 2017, theEuropean Commissionstated that "EU institutions should become open source software users themselves, even more than they already are" and listed open source software as one of the nine key drivers of innovation, together withbig data,mobility,cloud computingand theinternet of things.

In 2020, theEuropean Commissionadopted itsOpen Source Strategy 2020-2023,including encouraging sharing and reuse of software and publishing Commission's source code as key objectives. Among concrete actions there is also to set up an Open Source Programme Office in 2020and in 2022 it launched its own FOSS repositoryhttps://code.europa.eu/.

In 2021, theCommission Decision on the open source licensing and reuse of Commission software (2021/C 495 I/01)was adopted, under which, as a general principle, the European Commission may release software underEUPLor another FOSS license, if more appropriate. There are exceptions though.

In May 2022,theExpert group on the Interoperability of European Public Servicescame published 27 recommendations to strengthen the interoperability of public administrations across the EU. These recommendations are to be taken into account later in the same year in Commission's proposal of the"Interoperable Europe Act".

Production

See also:Open-source software development

Issues and incidents

GPLv3 controversy

While copyright is the primary legal mechanism that FOSS authors use to ensure license compliance for their software, other mechanisms such as legislation, patents, and trademarks have implications as well. In response to legal issues with patents and theDigital Millennium Copyright Act(DMCA), the Free Software Foundation releasedversion 3 of its GNU General Public License(GNU GPLv3) in 2007 that explicitly addressed the DMCA and patent rights.

After the development of the GNU GPLv3 in 2007, the FSF (as the copyright holder of many pieces of the GNU system) updated manyof the GNU programs' licenses from GPLv2 to GPLv3. On the other hand, the adoption of the new GPL version was heavily discussed in the FOSS ecosystem,several projects decided against upgrading to GPLv3. For instance theLinux kernel,theBusyBoxproject,AdvFS,Blender,and theVLC media playerdecided against adopting the GPLv3.

Apple,a user ofGCCand a heavy user of bothDRMand patents, switched the compiler in itsXcodeIDE from GCC toClang,which is another FOSS compilerbut is under apermissive license.LWNspeculated that Apple was motivated partly by a desire to avoid GPLv3.TheSambaproject also switched to GPLv3, so Apple replacedSambain their software suite by a closed-source, proprietary software alternative.

Skewed prioritization, ineffectiveness and egoism of developers

See also:Issue tracking system

Leemhuis criticizes theprioritizationof skilled developers who − instead of fixing issues in already popular open-source applications and desktop environments − create new, mostly redundant software to gain fame and fortune.

He also criticizes notebook manufacturers for optimizing their own products only privately or creatingworkaroundsinstead of helping fix the actual causes of the many issues with Linux on notebooks such as the unnecessary power consumption.

Commercial ownership of open-source software

Mergers have affected major open-source software.Sun Microsystems(Sun) acquiredMySQL AB,owner of the popular open-sourceMySQLdatabase, in 2008.

Oracle in turn purchased Sun in January 2010, acquiring their copyrights, patents, and trademarks. Thus, Oracle became the owner of both the most popular proprietary database and the most popular open-source database. Oracle's attempts to commercialize the open-source MySQL database have raised concerns in the FOSS community.Partly in response to uncertainty about the future of MySQL, the FOSS communityforkedthe project into newdatabase systemsoutside of Oracle's control. These includeMariaDB,Percona,andDrizzle.All of these have distinct names; they are distinct projects and cannot use the trademarked name MySQL.

Legal cases

Oracle v. Google

Main article:Google LLC v. Oracle America, Inc.

In August 2010,OraclesuedGoogle,claiming that its use ofJavainAndroidinfringed on Oracle's copyrights and patents. In May 2012, the trial judge determined that Google did not infringe on Oracle's patents and ruled that the structure of the Java APIs used by Google was not copyrightable. The jury found that Google infringed a small number of copied files, but the partiesstipulatedthat Google would pay no damages.Oracle appealed to theFederal Circuit,and Google filed across-appealon the literal copying claim.

As part/driver of a new socio-economic model

Main article:Open source

See also:Commons-based peer production,Free content,Sharing economy,andPost-scarcity economy

By defying ownership regulations in the construction and use of information—a key area of contemporarygrowth—theFree/Open Source Software (FOSS) movementcountersneoliberalismandprivatizationin general.

By realizing the historical potential of an "economy of abundance"for thenew digital world,FOSS may lay down a plan for political resistance or show the way towards a potentialtransformationofcapitalism.

According toYochai Benkler,Jack N. and Lillian R. Berkman Professor for Entrepreneurial Legal Studies atHarvard Law School,free software is the most visible part of a new economy ofcommons-based peer productionof information, knowledge, and culture. As examples, he cites a variety of FOSS projects, including both free software and open-source.

See also

• Contributing guidelines
• FLOSS Manuals
• FLOSS Weekly
• Free software movement
• Free-software license
• Free and open-source graphics device driver
• List of free and open-source software packages
• List of formerly proprietary software
• Open-source license
• Openwashing
• Outline of free software

References

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Further reading

• Barr, Joe (1998)."Why" Free Software "is better than" Open Source "".Free Software Foundation.Archived fromthe originalon 2007-07-03.Retrieved2007-11-25.
• Berry, David (2008).Copy, Rip, Burn: The Politics of Copyleft and Open Source(1 ed.). London: Pluto Press. p. 272.ISBN978-0745324142.Archivedfrom the original on 2021-07-09.Retrieved2021-03-25.
• Salus, Peter H. (March 28, 2005)."A History of Free and Open Source".Groklaw.Archived fromthe originalon 2015-09-24.Retrieved2015-06-22.
• Vetter, G. (2009)."Commercial Free and Open Source Software: Knowledge Production, Hybrid Appropriability, and Patents".Fordham Law Review.77(5): 2087–2141.Archivedfrom the original on 2012-04-24.Retrieved2011-10-23.
• Wheeler, David A. (May 8, 2014)."Why Open Source Software / Free Software (OSS/FS, FLOSS, or FOSS)? Look at the Numbers!".DWheeler.com.Archivedfrom the original on 2015-06-21.Retrieved2015-06-22.