1.3 Open Source Software and Licensing
Regardless of whether you have to pay for the software or not, there are four criteria which constitute free software. Richard Stallman describes these criteria as "the four essential freedoms", the counting of which he starts from zero:
0) "The freedom to run the program as you wish, for any purpose (freedom 0)." -Where, how and for what purpose the software is used can neither be prescribed nor restricted. 1) "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." -Everyone may change the software according to their ideas and needs. This in turn presupposes that the so-called source code, i.e. all files of which a software consists, must be available in a form readable by programmers. And, of course, this right applies to a single user who may want to add a single feature, as well as to software companies that build complex systems such as smartphone operating systems or router firmware. 2) "The freedom to redistribute copies so you can help others (freedom 2)." -This freedom explicitly encourages each user to share the software with others. It is therefore a matter of the widest possible distribution and thus the widest possible community of users and developers who, on the basis of these freedoms, further develop and improve the software for the benefit of all. 3)"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."
Six possible combinations and licenses offered by CC:
1) CC BY ("Attribution") 2) CC BY-SA ("Attribution-ShareAlike") 3) CC BY-ND ("Attribution-NoDerivatives") 4) CC BY-NC ("Attribution-NonCommercial") 5) CC BY-NC-SA ("Attribution-NonCommercial-ShareAlike") 6) CC BY-NC-ND ("Attribution-NonCommercial-No Derivatives")
Creative Commons (CC)
A global nonprofit organization that enables sharing and reuse of creativity and knowledge through the provision of free legal tools. The focus of the rights assignment goes back from the distributor to the author.
Under which license (including version) is Apache HTTP Server application available?
Apache License 2.0
CC BY-NC-SA ("Attribution-NonCommercial-ShareAlike")
As BY-NC, except that the work may only be shared under the same conditions (i.e. a copyleft-like license).
CC BY-SA ("Attribution-ShareAlike")
As CC BY, except that the modified work may only be distributed under the same license. The principle reminds of the copyleft, because the license is "inherited" here as well.
Under which license (including version) is Wikipedia articles (English) application available?
Creative Commons Attribution Share-Alike license (CC-BY-SA)
You have written a web application and published it under a free license. How can you earn money with your product? Name three possibilities.
Dual licensing, e.g. by offering a chargeable "Business Edition" Offering hosting, service, and support Developing proprietary extensions for customers
FOSS for
Free and Open Source Software
What does the abbreviation FLOSS stand for?
Free/Libre Open Source Software
FLOSS for
Free/Libre and Open Source Software
Covers selling access to hosted software
GNU Affero General Public License (AGPL)
Extends freedom principles to software documentation
GNU Free Documentation License (FDL)
Free Software Foundation (FSF) has formulated the
GNU General Public License (GPL) as one of the most important licenses for free software, which is used by many projects, e.g. the Linux kernel. Makes recommendations for or against third-party licenses, and affiliated projects such as GPL-Violations.org investigate suspected violations of free licenses.
Governs the combination of free software with modifications made to code where the source code for the modifications do not have to be released to the public
GNU Lesser General Public License (LGPL)
Under which license (including version) is MySQL Community Server application available?
GPL 2.0
Which of the following licenses would you call copyleft?
GPL version 3 CC BY-SA
You want to release your software under the GNU GPL v3. What steps should you follow?
If necessary, secure yourself against the employer with a copyright waiver, for example, so that you can specify the license. Add a copyright notice to each file. Add a file called COPYING with the full license text to your software. Add a reference to the license in each file.
Under which license (including version) is the GIMP application available?
LGPL 3: GNU Lesser General Public License v3
CC BY-ND ("Attribution-NoDerivatives")
Like CC BY, except that the work may only be passed on unmodified.
Under which license (including version) is Mozilla Firefox application available?
Mozilla Firefox
Name three examples of free software, which are also offered as "Business Edition", e.g. in a chargeable version.
MySQL, Zammad, Nextcloud
The 2-Clause BSD License, also called Simplified BSD License or FreeBSD License, proves how reduced such a permissive license can be. In addition to the standardized liability clause, which protects developers from liability claims arising from damage caused by the software, the license consists of only the following two rules:
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1) Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2) Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
Which of the following licenses would you call permissive?
Simplified BSD License CC BY
Why did the Free Software Foundation release the GNU Affero General Public License (GNU AGPL) as a supplement to the GNU GPL?
The GNU AGPL closes a license gap that arises especially with free software hosted on a server: If a developer makes changes to the software, he is not obliged under the GPL to make these changes accessible, since he allows access to the program, but does not "redistribute" on the program in the GPL sense. The GNU AGPL, on the other hand, stipulates that the software must be made available for download with all changes.
CC BY ("Attribution")
The free license that allows anyone to edit and distribute the work as long as they name the author.
CC BY-NC-ND ("Attribution-NonCommercial-NoDerivatives")
The most restrictive license: the distribution is allowed with attribution of the author, but only unchanged and under non-commercial conditions.
CC BY-NC ("Attribution-NonCommercial")
The work may be edited and distributed by naming the author, but only under non-commercial conditions.
The Berkeley Software Distribution (BSD) is a variant of the
Unix operating system originally developed at the University of Berkeley, which later gave rise to free projects such as NetBSD, FreeBSD and OpenBSD. The licenses underlying these projects are often referred to as permissive.
software is not a physical product, but a
digital product.