User:Ashawley/Proprietary software

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 opposite 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. Legal means of enforcement include copyright (possibly with a restrictive software license) 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. Use of software is enforced by contract law through either an explicit software license agreement or by shrink wrap licensing or click-wrap.

Relation to commercialisation
"Proprietary software" is not synonymous with "commercial software", though the industry commonly confuses the term, as does the free software community.

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.

Literal and legal meanings
The literal legal meaning 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. Software which is not proprietary, like public domain software and software under a permissive license, can become proprietary software by distributing compiled, binary versions of the program without making the source code available.

The free software movement's founder Richard Stallman sometimes uses the term "user-subjugating software" to describe proprietary 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 provides no source code. The Open Source Initiative uses the term "proprietary software" and "closed source software".

Free software licences use the same laws used by proprietary software, but to preserve the rights to use, copy and modify the software. This technique is used with copyleft, but with other software as well. Free software companies and projects are also joining into patent pools like the Patent Commons and the Open Invention Network. See software patents and free software.

Rationale
Proponents of commercial proprietary software argue that requiring users to pay for software as a product increases funding for the research and development of software. For example, Microsoft says that per-copy fees maximise the profitability of software development.

Proprietary software is said to create greater commercial activity over free software, especially in regard to market revenues.

Problems
A dependency on the future versions and upgrades for a proprietary software package 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 may have no recourse if problems are found with the software. Proprietors can fail to improve and support software because of business problems. 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; or migrate to either competing systems with longer support life cycles or to FOSS-based systems.

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. 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.

Free software that depends on proprietary software is considered "trapped" by the Free Software Foundation. This includes software written only for Microsoft Windows, or software that could only run on Java, before it became free software.

Examples
Well known examples of proprietary software include Microsoft Windows, RealPlayer, MATLAB, iTunes, Adobe Photoshop, Adobe Flash Google Earth, Mac OS X, Skype, Mathematica, WinZip and some versions of Unix.

Software distributions considered as proprietary may in fact incorporate a "mixed source" model including both free and non-free software in the same distribution. 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.

The end-user license agreement (EULA) for software can restrict user rights even further than traditional copyright. For example, the EULA for Microsoft Windows states that the the software "is licensed, not sold". Restrictions to the software's use include installing to one computer for a basic license, and limits the number of connections with "computers or other electronic devices". With the release of Windows Server 2003, Microsoft wanted to require companies to purchase client access licenses for each machine that connects to a server running the software. Previously the client licenses were only required for connecting systems running older versions of Windows.

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 licenses or non-disclosure agreements from redistributing modifications or sharing the software. Examples include Pine, the Microsoft Shared source license program, and certain proprietary implementations of Secure Shell. Microsoft's Reference Source License (Ms-RSL) and Limited Public License (Ms-LPL) are examples of a license where the source code is made available but it remains proprietary software.

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 license or released to the public domain) allows anyone to make proprietary redistributions.

Proprietary software that is no cost is called freeware. Shareware, like freeware, is proprietary software available at zero price, but differs in being gratis 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 the source code released to the public domain either by its author or copyright holder and is therefore free software, and no longer proprietary software.

For certain proprietary software where the user can access source code, such as online applications (for example, 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. According to Jonathan Zittrain, the emergence of "closed devices" and online applications, like the iPhone, Facebook and Google apps, have made the Internet to become far more proprietary than early versions of Microsoft software.