Free software, software libre, or libre software〔See (【引用サイトリンク】title=What is Free Software )〕 is computer software that gives users the freedom to run the software for any purpose as well as to study, change, and distribute the software and the adapted versions.〔(Free Software Movement ) (gnu.org)〕〔(Philosophy of the GNU Project ) (gnu.org)〕〔(What is free software ) (fsf.org)〕〔(【引用サイトリンク】title=GNU Press - Free Software Foundation Online Shop - Buy GNU t-shirts, books, stickers and stuffed gnu toys )〕〔 The right to study and modify free software gives full access to its source code. For computer programs which are covered by copyright law this is achieved with a software license where the author grants users the aforementioned freedoms. Software which is not covered by copyright law, such as software in the public domain is free if the source code is in the public domain (or otherwise available without restrictions). Other legal and technical aspects such as software patents and Digital restrictions management can restrict users in exercising their rights, and thus prevent software from being free. Free software may be developed collaboratively by volunteer computer programmers or by corporations; as part of a commercial, for-profit activity or not.
Free software is a matter of liberty, not price: users, individually or collectively, are free to do what they want with it – this includes the freedom to redistribute the software free of charge, or to sell it (or related services such as support or warranty) for profit.〔(Selling Free Software ) (gnu.org)〕 Free software thus differs from proprietary software (such as Microsoft Office, Google docs or iWork from Apple), which prevents users from studying, changing and sharing the software. Free software is also different from freeware, which is simply a category of freedom-restricting proprietary software which does not require payment for use. Proprietary software (including freeware) use restrictive software licences or EULAs and usually do not provide access to the source code. Users are thus prevented from changing the software, and this results in the user relying on corporations (such as Microsoft) to provide updates, help, and support. This situation is called vendor lock-in. Users often can't reverse engineer, modify, or redistribute proprietary software.〔〔
The term "free software" was coined in 1985 by Richard Stallman when launching the GNU Project - a collaborative effort to create a freedom-respecting operating system - and the Free Software Foundation, or FSF. The FSF's Free Software Definition〔 states that users of free software are "free" because they do not need to ask for permission to use the software.〔
== History ==
From the 1950s up until the early 1970s, it was normal for computer users to have the ''software freedoms'' associated with free software. Software was commonly shared by individuals who used computers and by hardware manufacturers who welcomed the fact that people were making software that made their hardware useful. Organizations of users and suppliers, for example, SHARE, were formed to facilitate exchange of software. By the early 1970s, the picture changed: software costs were dramatically increasing, a growing software industry was competing with the hardware manufacturer's bundled software products (free in that the cost was included in the hardware cost), leased machines required software support while providing no revenue for software, and some customers able to better meet their own needs did not want the costs of "free" software bundled with hardware product costs. In ''United States vs. IBM'', filed January 17, 1969, the government charged that bundled software was anti-competitive.〔 While some software might always be free, there would henceforth be a growing amount of software produced primarily for sale. In the 1970s and early 1980s, the software industry began using technical measures (such as only distributing binary copies of computer programs) to prevent computer users from being able to study or adapt the software as they saw fit. In 1980 copyright law was extended to computer programs.
In 1983, Richard Stallman, one of the original authors of the popular Emacs program and a longtime member of the hacker community at the MIT Artificial Intelligence Laboratory, announced the GNU project, the purpose of which was to produce a completely non-proprietary Unix-compatible operating system, saying that he had become frustrated with the shift in climate surrounding the computer world and its users. In his initial declaration of the project and its purpose, he specifically cited as a motivation his opposition to being asked to agree to non-disclosure agreements and restrictive licenses which prohibited the free sharing of potentially profitable in-development software, a prohibition directly contrary to the traditional hacker ethic. Software development for the GNU operating system began in January 1984, and the Free Software Foundation (FSF) was founded in October 1985. He developed a free software definition and the concept of "copyleft", designed to ensure ''software freedom'' for all.
Some non-software industries are beginning to use techniques similar to those used in free software development for their research and development process; scientists, for example, are looking towards more open development processes, and hardware such as microchips are beginning to be developed with specifications released under copyleft licenses (see the OpenCores project, for instance). Creative Commons and the free culture movement have also been largely influenced by the free software movement.
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』