Glossary - General Descriptions about Some Open Source Related Terms:
See also Validos frequently asked questions about open source software.
Term: Copyleft
A copyleft clause in software license stipulates that any changes made to the software have to be licensed under
the same conditions than the original software in case of redistribution or relicensing. All open source licenses don't have a copyleft clause and there are several types of copyleft clauses. Copyleft clauses can be divided into e.g. weak and strong depending on the circumstances in which the conditions must be followed (strong clauses must be followed in more numerous circumstances). The best known license embodying a copyleft clause is the GNU General Public License 2 or GPL 2.
Typically a copyleft clause applies when the original software is redistributed. In order to have a right to distribute the original software with modifications the distributor must distribute the modifications under the same conditions than the original software.
Copyleft clause is often (erroneously) assumed to have an automatical effect that can lead to "contamination" i.e. that any software combined with copyleft licensed software could somehow be transformed to be under a copyleft license. However, this kind of mechanism is not written into any known license. The clear result from not following the clause is a copyright infringement and/or possibly penal sanctions.
Example: Mozilla Public License 1.1 or MPL 1.1embodies so-called weak copyleft clause. According to it, if files in software distribution are modified, the modifications must also be licensed under MPL license. Failing that, the original software may not be distributed with the modifications. The modifying can also be performed by for example copying a file or part of a file into another, self made file.
Synonyms: reciprocality, viral effect, hereditary effect.
Term: License (software license)
Software license means a permit to utilize a software, that is to say, the conditions according which the software may be utilised. A license may be constured as an agreement between the holder of the rights to the software and utilizer of the software (this is the predominant case under Finnish law) or another type of permission (in some countries license / permit to utilize is governed by different legal rules than a contract). Open source software is licensed under so-called open source licenses.
Example: Apache 2.0 is a license. It has been created by Apache Software Foundation (an American foundation) and it is used as a license for the software projects of the foundation and it is also more widespread. If one wishes to use Apache 2.0 licensed software one must obey the conditions of Apache 2.0.
Synonyms: -
Term: Permissive License
So called permissive open source licenses give a permission to use the software without major restrictions. The conditions usually relate only to maintaining and publishing the copyright and license information. These licenses enable modifying and distributing the software also as a part of a commercial software under a proprietary license. Common permissive licenses are BSD ja MIT License with their different variations.
Synonyym: academic license
Term: Source code
Source code is a computer code written by a human (programmer). Before source code can be run in a computer it must be compiled or interpreted into code computer understands (e.g. binary code). To develop, modify or patch a software the source code is needed
Synonyms: -
Term: Open Source Software
Open source software is a software that is published under so-called open source software license. Conditions of this type of software allow copying, modifying and redistributing the software quite freely. Open Source Initiative (OSI) keeps a definition of open source software. Free Software Foundation (FSF) uses the consept ”free software”,which means from a commercial users viewpoint much the same thing.
Additionally terms OS, OSS, FOSS, FLOSS are used. They mean much the same thing. FLOSS = Free and Libre and Open Source Software.
Synonym: free software
Term: Fossology
Fossology is a tool running on a Linux platform for examinig software source code. Fossology was originally developed by HP for its internal use and now it is developed as a open source project supported by the Linux Foundation (fossology.org). Fossology identifies several hundreds of licenses and license clauses and variations of those. Validos uses Fossology as a tool for examining source code.
Term: Intellectual property rights
Intellectual property righs in most cases are intended for protection of a legal right to results of creative work and/or commercial investment. Typical forms of protection are copyright, desing, trademark and patent. The most common form of software protection is copyright. Open source licensing is based on reserving the copyright to the author and after that giving a broad license.
Right to a trademark can protect a trademark of the software or similar. A patent can protect a tecnical invention implemented in software. Patenting computer programs or algorithms is more common in United States, Australia and Japan, but now increasingly possible also in Europe.
Synonyms: IPR (intellectual property rights)
Termi: Public domain
By public domain (PD) notice an author relinquishes hers/his rights to a copyright and places the work into a entirely free use of the public (into so-called public domain). PD-software must not be confused with open source software whose licensing is based on the permit to use granted by the owner of the copyright.
Term: Freeware, shareware
Freeware is a software which can be loaded and utilized without license payment. Freeware license is usually a proprietary type license. Shareware is otherwise similar software than freeware but a fee is required in different ways in order to use the software (usually at least trial period is free). Freeware or shareware does not mean the same as open source.
Term: Commercial use, use in businesses
Commercial use of a software is a vague term. All use by a company can be seen as a commercial use (broad definition) or then just copying and distributing a copy for a fee (limited definition). There are numerous possibilities between these edge-cases. At Validos we use a term "used in businesses" which covers all conceivable use of software by a company. |
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