[Add to favorites] Ten misunderstandings about GNU General Public Authorization (GPL)

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GNU/GPL may be the most misunderstood software protocol. Let's talk about the top ten common mistakes.
1) GPL infected everything.
Modifications to derivative works on the GNU/GPL software must also be published on a GPL basis. However, independently developed software is not affected by GPL. Therefore, even in the same software, GPL components can coexist with components released by other protocols. GPL software can be compatible with other software in any system.
2) the legal force of GPL cannot be enforced.
GPL has the same legal force as other software protocols. There have been cases in the United States and Germany that violate GPL laws and punishments. [Of course, it can be said that GPL does not have legal force in China. I think for most programmers, this is not a legal issue.]
3) GPL is not charged.
GPL software can sell for money [and you can sell for whatever price you like]. However, the price of source code cannot exceed the release cost.
4) Not free, rather dead.
Section 7th of GPL, "if the result of a court decision, patent infringement claim or any other reason (not limited to patent disputes, in the event that your conditions (whether caused by court orders, agreements or other means) conflict with this authorization provision, they do not exempt you from complying with this authorization provision. If you cannot publish in accordance with the obligations and other relevant obligations under this authorization at the same time, the result is that you are not allowed to publish this process ." However, this does not mean that any possible patent authorization restrictions or potential legal restrictions will inevitably trigger this provision.
5) The derivative works only need to publish the modified Code.
Derivative works need to publish all source code.
6) you only need to provide the source code for the GPL file, no matter how the code is used.
GPL not only provides source code and related interface definition files, but also provides methods for use, such as compiling and installing scripts.
7) The publisher does not need to propose source code.
The GPL publisher may not wrap the source code in the compiled software, but it must explicitly indicate that the source code will be provided in response to the user's requirements.
8) the publisher "only" needs to propose source code.
If the GPL publisher proposes to provide source code, this guarantee must be valid for three years and for anyone.
9) The publisher only needs to provide the GPL link.
The publisher must provide the full text of GPL. The user does not need to connect to the full text anytime, anywhere [if one day, GFW will drink too much...].
10) What constitutes a release version.
In the new version of GPL, "Distribution" has been replaced with "propagate" and "convey ". But what constitutes a release, especially in different legal and cultural systems, is still a confusing issue. Here is a reminder, which is not discussed in detail.
This article mainly references an article on IT Manager's Journal last year ([url] http://www.itmanagersjournal.com/feature/1287#/url.pdf). If you are interested, you can further check the original text and the new GPL version.