The open source definition gives the basic nature of open source software. Unfortunately, the term open source has been misused, and due to its descriptive nature, it cannot be protected as a trademark (which is our first choice). Because the community needs a reliable way to determine whether a piece of software is truly open source software. OSI has registered a certification mark, OSI Certified, for this purpose. If you see this mark on a piece of software, then the software must have been released under a license that complies with the open source definition; otherwise, the publisher is abusing the mark and violating the law.

A license confers specific rights to the user, but also stipulates restrictions that the user must abide by. Open source software often uses open source licenses. All open source licenses are certified by the Open Source Initiative (OSI).

Approved Licenses

The following licenses meet the definition of open source and have been approved for use with OSI Certified open source software. Permits with no approval date given were approved before January 1, 1999.

* The GNU General Public License (GPL)

* The GNU Library (Lesser) General Public License (LGPL)

* The X Consortium License

* The Artistic License

* The Mozilla Public License (MPL)

* TheQPL

* OpenLDAPPublic License

Other licenses that meet the definition include: libpng License, zlib License, IJG JPEG License, and BSD License. According to different usage conditions, open source software licenses can be divided into three categories (with decreasing severity)

1. When the code of the open source software is redistributed, the source code must also be made public under the same license.

Represents license type: GPL, AGPL

Example: GPL

GNU General Public License Agreement (English: GNU General Public License, referred to as GNU GPL or GPL), is a widely used free software license originally written by Richard Stallman for the GNU Project. GPL is the main license of the Free Software Foundation, and the commonly used versions are the 2nd version in 1991 and the 3rd version in 2007.

The GPL grants the program recipient the following rights: freedom to run the program for any purpose; freedom to redistribute copies; freedom to improve the program and publicly release improvements (provided the source code is available). The GPL license agreement has strong copyleft and a "viral effect", which means that if the user wants to redistribute GPL-licensed software or works based on GPL-licensed software (for example, as part of the user's product), then it must be Distribution under terms that are not stronger than the GPL license restrictions, that is, it must also be open source and free. This is the so-called "infectiousness". The GPL license agreement is currently the most popular open source license and is used by many famous open source software, such as the Linux kernel, MySQL database, etc.

2. When using the code of the open source software and modifying the open source code before distributing it, the source code must be disclosed under the same license.

Represents license types: LGPL, CPL, CDDL, CPL, MPL, etc.

Example: LGPL

GNU Lesser General Public License Agreement (English: GNULibrary General Public License (LGPL for short), also known as the GNU Library General Public License, is also from the Free Software Foundation and has version 2.1 in 1999 and version 3.0 in 2007.

LGPL is a loose version of GPL, which reserves fewer rights for products than GPL. In general, LGPL is suitable for open source libraries or frameworks used in non-GPL or non-open source products. Because of GPL requirements, products that use GPL code must also use the GPL protocol, and developers are not allowed to use GPL code for commercial products. LGPL circumvents this restriction. LGPL has weak copyleft effect and is more business-friendly: dynamic linking is allowed; static linking is conditionally allowed. If the LGPL-licensed code itself is modified, then redistribution must use an LGPL or GPL license. 3． There are no special restrictions when using the code of this open source software (including modifications) and redistributing it, and you only need express permission.

Represents the license type: ASL, BSD, MIT, etc.

Example: MIT

The MIT protocol may be the most lenient among the major open source protocols. Introduced by the Provincial Polytechnic in 1988, it is also known as the X11 license or the X license, and has many variants. The core terms are: The software and related documentation are free to everyone and may be disposed of at will, including using, copying, modifying, merging, publishing, distributing, sublicensing, or selling. The only restriction is that the above copyright and licensing notices must be included with the software. This means: You are free to use, copy, modify and use it in your own projects. Can be distributed for free or used for profit. The only restriction is that a permission statement must be included. The MIT license is the most permissive of all open source licenses and has no restrictions except that it must contain a license statement.

Example: BSD

The BSD license originates from the University of California, Berkeley, and the owner is the Board of Regents of the University of California. Compared with other licenses, from the GNU General Public License (GPL) to the highly restrictive Copyright (Copyright), the BSD license is relatively loose and even closer to the public domain. In fact, the BSD license is considered a copycenter (intermediate copyright), between the standard copyright and the GPL's copyleft. Take it down to the copy center and make as many copies as you want. It can be said that GPL forces subsequent versions to be free software, while subsequent versions of BSD can choose to continue to be BSD or other free software terms or closed software, etc.

There are many versions of this agreement, and different BSD licenses are issued by different projects. For example, there are two main versions of Apple's BSD license and the BSD license of the 4.4BSD Lite derivative operating system, the new BSD protocol and the Simple BSD protocol, both of which have been modified to be compatible with the GPL and recognized by open source organizations. The new BSD agreement (3-clause agreement) has no restrictions on software distribution except that it needs to include a copyright notice and disclaimer. In addition, the agreement also prohibits endorsing derivative products in the name of the developer, but the simple BSD agreement has deleted this clause. 1． Email the license to license-approval@opensource.org. In the email, indicate whether you would like to have the license sent to the license discussion list with your signature or anonymously. (We are willing to consider licenses that do not want to be sent out at all, but since review by the community is an important part of approval, we will have to send the license privately to reviewers: therefore, no comments are sent to the license Approval of licenses on the license discussion list takes longer and usually involves more communication with you)

2. If we find that your license does not meet the definition of open source, we will work with you to resolve the issue.

3. In the meantime, we'll be keeping an eye on the license forum list and working with you to resolve any questions you have that aren't included.

4. As part of this process, we will also seek external legal advice on licensing issues.

5. Once the license meets the open source definition and has been fully discussed on the license forum or other reviewers have raised no important questions, we will notify you that the license has been approved and it has been copied to our website and has been added to the license list below.