Open source is already very common in today's software industry, but does open source means that users can do for open source? the answer is negative. Open source sports also have their own game rules and moral guidelines. Do not follow these rules not only harm the healthy development of open source movements, but also cause the illegal and market losses, more likely to fall into legal disputes and compensation.
There are many open source protocols in today, and there are currently 58 of the Open Source Initiative organizations through approved open source agreements. We are all approved agreements approved by the common open source protocol such as BSD, GPL, LGPL, MIT, etc.. If you want to open your own code, it is best to choose these approved open source protocols.
Here we look at the four most common open source protocols and their applicable scope for developers / manufacturers who are ready to open or use open source products.
BSD open source protocol
The BSD open source protocol is an agreement given to the user. Basically users can "for what they want", they can use free use, modify the source code, and can also be released as an open source or proprietary software.
But "For what you want", when you release the code using the BSD protocol, or when you use the BSD protocol code, you need to meet three conditions:
1. If the released product contains the source code, you must have the BSD protocol in the original code in the source code.
2. If the release is just binary library / software, you need to include the BSD protocol in the original code in the documentation and copyright declarations of the class library / software.
3. It is not possible to use the authors / institution names of open source code and the name of the original product.
BSD code encourages code sharing, but requires respect for the copyright of the code author. BSD is also allowed to use or develop commercial software releases and sales on BSD code, which is also allowed to use or develop commercial software on the BSD code. Therefore, it is a friendly agreement with business integration. Many companies have preferred BSD protocols when they choose open source products, as they can fully control these third-party code, and can be modified or secondary during it when necessary.
Apache licence 2.0
Apache Licne is an agreement adopted by the famous non-profit open source organization Apache. The agreement is similar to BSD, which also encourages code sharing and respect the copyright of the original author, and allows code to modify, then release (as an open source or commercial software). The conditions that need to be met are similar to BSD:
1. Users who need to give the code A apache license
2. If you modify the code, you need to explain it again.
3. In the extended code (modified and active code derived code) requires the protocols, trademarks, patent declarations, and other original authors that require the original code to include.
4. If a NOTINE file is required in the NOTICE file, you need to bring Apache Licne in the Notice file. You can add your license in Notice, but it is not possible to make changes to Apache Licence.
Apache Licne is also a license for commercial applications. Users can also modify the code when needed to meet the needs and publish / sell them as an open source or commercial product.
GPL
Linux we are familiar with is GPL. GPL protocols and BSD, Apache Licne, etc. are very different. The starting point of the GPL is the open source / free use of the code and the open source / free use of the reference / modification / derivative code, but does not allow the modified and derived code as a closed source of commercial software release and sales. This is why we can use a free Various Linux, including a wide range of individuals, organizations, and commercial software companies on a variety of personal, organizations, and commercial software companies on Linux and Linux.
The main content of the GPL protocol is as long as it is used in a software ("Use" to specify the class library reference, the modified code or the derivative code) GPL protocol, the software product must also use the GPL protocol, which must be an open source and free . This is the so-called "contagious". The GPL protocol product is not available as a separate product, and you can also enjoy a free advantage. Since the GPL strict requirements for software products that use the GPL class library must use the GPL protocol, for the open source code, commercial software, commercial software, or a confidentiality required for the code, is not suitable for integrated / adoption of the base library and secondary development. .
Other details This time is required to be similar to BSD / Apache, such as re-release.
LGPL
LGPL is an open source protocol for the GPL to use design designed for class libraries. And GPL requires any software that uses / modify / derived GPL class libraries must be different from GPL protocols. LGPL allows business software to use the LGPL class library through class library reference (LINK) without requiring code of open source business software. This allows open source code using the LGPL protocol to be referenced and published as a class library.
However, if you modify the code or derived of the LGPL protocol, all modified code involve additional code and derived code involving the modified part must adopt the LGPL protocol. Therefore, the open source code of the LGPL protocol is well suited as a third-party library, but it is not suitable for the use of the LGPL protocol code to do secondary development by modifying and derived by modifying and derived.
GPL / LGPL guarantees the original author's intellectual property rights to avoid copying and developing a similar product with open source code.
Latest GPL3
