Proprietary software
From Wikipedia, the free encyclopedia
Proprietary software is any computer software with restrictions on use or private modification, or with restrictions judged to be excessive on copying or publishing of modified or unmodified versions. The term proprietary software is thus the antonym of free software, generally speaking. These restrictions are placed on it by one of its proprietors. Similar terms include "closed-source software" and "non-free software".
These restrictions are enforced by either legal or technical means, or both. The most common form of technical restriction is by releasing programs that are only computer-readable (for example, in binary format), and withholding the human-readable source code. Means of legal enforcement can involve copyright (with a restrictive software licence) and patents. The source code of such programs is usually regarded as a trade secret by the owner. Access to source code by third parties commonly requires the party to sign a non-disclosure agreement.
The free software movement's founder Richard Stallman sometimes uses the term "user subjugating software", while Eben Moglen sometimes talks of "unfree software". The term "non-free" is often used by Debian developers to describe any software whose license does not comply with Debian Free Software Guidelines, and they use "proprietary software" specifically for non-free software that provide no source code. The Open Source Initiative prefers the term "closed source software". Proprietary software vendors usually do not use this term[citation needed] or use it with another meaning[citation needed].
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[edit] Relation to commercialisation
"Proprietary software" is not synonymous with "commercial software". Proprietary software can be distributed at no cost or for a fee, and free software can be distributed at no cost or for a fee. The difference is that whether or not proprietary software can be distributed, and what the fee would be, is at the proprietor's discretion. With free software, anyone who has a copy can decide whether, and how much, to charge for a copy or related services.
[edit] Literal and legal meanings
The literal legal mean of "proprietary" in relation to software is that it has an owner who can exercise control over what users can do with the software.
Exclusive legal rights to software by a proprietor are not required for software to be proprietary, since public domain software and software under a permissive licence can become proprietary software by distributing compiled (binary) versions of the program without making the source code available. Proprietary software includes freeware and shareware.
Software distributions considered as proprietary may in fact incorporate a "mixed source" model including both free and non-free software in the same distribution.[1] Most if not all so-called proprietary UNIX distributions are mixed source software, bundling open source components like BIND, Sendmail, X Window System, DHCP, and others along with a purely proprietary kernel and system utilities.[2][3]
For some free software, the same laws used by proprietary software are used to preserve the freedoms to use, copy and modify the software. This technique is called copyleft.
[edit] Reasons for
Proponents of commercial proprietary software, like Microsoft, argue that requiring users to pay for software as a product increases funding for the research and development of software. They claim that per-copy fees maximise the profitability of software development.[4]
Proprietary software is said to create greater commercial activity over free software, especially in regard to market revenues.[5]
[edit] Reasons against
A dependency on future versions and upgrades can create "vendor lock-in", entrenching a monopoly position.
If the proprietor of a software package should cease to exist, or decide to cease or limit production or support for a proprietary software package, recipients and users of the package can be left at a disadvantage and have no recourse if problems are found with the software. Proprietors can fail to improve and support software because of business problems.[6] When no other vendor can provide support for the software, the ending of support for older or existing versions of a software package may be done to force users to upgrade and pay for newer versions.[7]
[edit] Semi-free software
Semi-free software, as defined by the Free Software Foundation, is software that is not free software, but comes with permission for individuals to use, copy, distribute, and modify (including distribution of modified versions) only for non-profit purposes.[8] Such software is also rejected by the Open Source Initiative and Debian.
PGP and Angband are examples of semi-free programs. The Free Software Foundation classifies semi-free software as non-free software, but draws a distinction between semi-free software and proprietary software.
[edit] Examples
Well known examples of proprietary software include Microsoft Windows, RealPlayer, iTunes, Adobe Photoshop, Mac OS X, WinZip and some versions of Unix.
Some free software packages are also simultaneously available under proprietary terms. Examples include MySQL, Sendmail and ssh. The original copyright holders for a work of free software, even copyleft free software, can use dual-licensing to allow themselves or others to redistribute proprietary versions. Non-copyleft free software (i.e. software distributed under a permissive free software licence or released to the public domain) allows anyone to make proprietary redistributions.
Some proprietary software comes with source code or provides offers to the source code. Users are free to use and even study and modify the software in these cases, but are restricted by either licences or non-disclosure agreements from redistributing modifications or sharing the software. Examples include Pine, the Microsoft Shared source licence program, and certain proprietary implementations of ssh.
Shareware, like freeware, is proprietary software available at zero price, but differs in that it is free only for a trial period, after which some restriction is imposed or it is completely disabled. Proprietary software which is no longer marketed by its owner and is used without permission by users is called abandonware and may include source code. Some abandonware has its source code placed in the public domain either by its author or copyright holder and is therefore free software, not proprietary software.
Microsoft's Ms-LPL is an example of a licence where the source code is made available but it remains proprietary software.
For certain proprietary software where the user can access source code, such as online applications (such as Internet forum software) or Java applications (where the source can be obtained by decompiling), some developers will obfuscate the source code in order to make it difficult for users to obtain the original code.
[edit] See also
- Commercial software
- Glossary of legal terms in computer technology
- Proprietary hardware
- Glossary of legal terms in technology
- Comparison of open source and closed source
[edit] References
- ^ Engelfriet, Arnoud (August/September 2006). "The best of both worlds". Intellectual Asset Management (IAM) (19). New Hibernia House, Winchester Walk, London Bridge, London SE1 9AG, United Kingdom: Gavin Stewart.
- ^ Loftus, Jack (2007-02-19). LinuxWorld: Managing mixed source software stacks. SearchEnterpriseLinux.com.
- ^ Tan, Aaron (2006-12-28). Novell: We're a 'mixed-source' company. CNET Networks, Inc.
- ^ The Commercial Software Model. Microsoft (May 2001). Retrieved on 2007-03-05.
- ^ Open Source Versus Commercial Software: Why Proprietary Software is Here to Stay. Sams Publishing (October 2005). Retrieved on 2007-03-05.
- ^ What happens when a proprietary software company dies?. NewsForge (October 2003). Retrieved on 2007-03-05.
- ^ Microsoft Turns Up The Heat On Windows 2000 Users. InformationWeek (December 2006). Retrieved on 2007-03-05.
- ^ Semi-free software, definition by the Free Software Foundation
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