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Open Source Free Licenses

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Open source software is software that is released under a license that allows users to study, change, and improve the software. Open source licenses are typically permissive, meaning that they allow users to use, modify, and distribute the software for any purpose.

  • MIT License is a permissive license that allows for free use, modification, and distribution of the software. It is the most popular open-source license in the world.

  • GNU General Public License (GPL) is a copyleft license that requires that all derivative works of the software be licensed under the GPL. This means that if you modify the software, you must make your modifications available to the public under the GPL. The GPL is the most popular copyleft license in the world.

  • Apache License 2.0 is a permissive license that is similar to the MIT License, but it includes a few additional restrictions. For example, the Apache License requires that you include the Apache License notice in all derivative works. The Apache License is a popular choice for open source projects that want to ensure that their software is used in a way that is compatible with the Apache Software Foundation's Code of Conduct.

  • BSD 2-Clause "Simplified" License is a permissive license that is similar to the MIT License, but it does not include a patent grant. This means that if you modify the software and add a patent claim, you are not required to license your modifications under the BSD 2-Clause License. The BSD 2-Clause License is a popular choice for open-source projects that want to avoid patent entanglements.

  • BSD 3-Clause "New" or "Revised" License is a permissive license that is similar to the BSD 2-Clause License, but it includes additional restrictions on the use of the software in commercial applications. The BSD 3-Clause License is a popular choice for open-source projects that want to ensure that their software is used in a way that is compatible with the BSD Software Distribution Guidelines.

Other opular open-source licenses

  • Academic Free License v. 3.0 (AFL-3.0) is a permissive license that allows for free use, modification, and distribution of the software. It is similar to the MIT License, but it includes a few additional restrictions, such as a requirement to include the AFL-3.0 license notice in all derivative works.

  • Adaptive Public License 1.0 (APL-1.0) is a copyleft license that allows for free use, modification, and distribution of the software. It is similar to the GPL, but it includes a few additional restrictions, such as a requirement to include the APL-1.0 license notice in all derivative works.

  • Apache Software License, version 1.1 (Apache-1.1) is an earlier version of the Apache License 2.0. It is similar to the Apache License 2.0, but it includes a few additional restrictions.

  • Common Development and Distribution License 1.0 (CDDL-1.0) is a copyleft license that is similar to the GPL. It is used by the Java Community Process (JCP) for the development of Java specifications and implementations.

  • Eclipse Public License version 2.0 (EPL-2.0) is a permissive license that is similar to the Apache License 2.0. It is used by the Eclipse Foundation for the development of Eclipse-based software.

  • GNU Affero General Public License version 3 (AGPL-3.0-only) is a copyleft license that is similar to the GPL. However, it requires that all users of the software be able to access the source code.

  • GNU General Public License version 2 (GPL-2.0) is a copyleft license that is similar to the GPL. However, it has a few minor differences.

  • GNU General Public License version 3 (GPL-3.0-only) is a copyleft license that is similar to the GPL. However, it has a few minor differences.

  • GNU Lesser General Public License version 2.1 (LGPL-2.1) is a weaker copyleft license than the GPL. It allows linking to libraries without affecting the license of the derivative work.

  • GNU Lesser General Public License version 3 (LGPL-3.0-only) is a weaker copyleft license than the GPL. It allows linking to libraries without affecting the license of the derivative work.

  • Mozilla Public License 2.0 (MPL-2.0) is a permissive license that is similar to the Apache License 2.0. The Mozilla Foundation uses it.

  • Microsoft Public License (MS-PL) is a permissive license that allows for free use, modification, and distribution of the software. It is similar to the MIT License, but it includes a few additional restrictions, such as a requirement to include the MS-PL license notice in all derivative works.

  • Microsoft Reciprocal License (MS-RL) is a permissive license that allows for free use, modification, and distribution of the software. It is similar to the MIT License, but it includes a few additional restrictions, such as a requirement to include the MS-RL license notice in all derivative works.

  • The 2-Clause BSD License (BSD-2-Clause) is a permissive license that is similar to the MIT License, but it does not include a patent grant. This means that if you modify the software and add a patent claim, you are not required to license your modifications under the BSD 2-Clause License. The BSD 2-Clause License is a popular choice for open-source projects that want to avoid patent entanglements.

  • The 3-Clause BSD License (BSD-3-Clause) is a permissive license that is similar to the BSD 2-Clause License, but it includes additional restrictions on the use of the software in commercial applications. The BSD 3-Clause License is a popular choice for open-source projects that want to ensure that their software is used in a way that is compatible with the BSD Software Distribution Guidelines.

  • Open Software License, version 1.0 (OSL-1.0) is a permissive license that allows for free use, modification, and distribution of the software. It is similar to the MIT License, but it includes a few additional restrictions, such as a requirement to include the OSL-1.0 license notice in all derivative works.

  • OpenLDAP Public License Version 2.8 (OLDAP-2.8) is a permissive license that allows for free use, modification, and distribution of the software. It is similar to the MIT License, but it includes a few additional restrictions, such as a requirement to include the OLDAP-2.8 license notice in all derivative works.

  • Hippocratic License 3.0 (HL3) is an ethical license for open-source communities. It requires that all derivative works of the software must be used in a way that is ethical and responsible. The HL3 license is a good choice for open-source projects that want to ensure that their software is used in a way that respects human rights and environmental protection.

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When choosing an open-source license for your project, it is important to consider the following factors:

  • The intended use of the software If you are developing software that will be used in a commercial setting, you may want to choose a license that is more restrictive, such as the GPL. If you are developing software that will be used for personal or non-commercial use, you may want to choose a more permissive license, such as the MIT License.

  • The community that you want to build around your project Some licenses are more popular than others, and some licenses are more likely to attract a certain type of developer. For example, the MIT License is a popular choice for projects that want to attract a wide range of developers, while the GPL is a popular choice for projects that want to build a community of developers who are committed to free software.

  • Your own legal and financial considerations Some licenses may have implications for your legal and financial liability. For example, the GPL requires that you make the source code of your software available to the public, which could make you vulnerable to patent infringement claims. If you are concerned about these risks, you may want to choose a more restrictive license.

Ultimately, the best way to choose an open-source license for your project is to consider your specific needs and goals carefully.

The license's popularity. Some licenses are more popular than others, which means that there is a larger community of developers who are familiar with them. This can make it easier to find help and support if you run into problems with your project. The license's compatibility with other licenses. If you are using code from other open-source projects, you must ensure the licenses are compatible. For example, you cannot use code licensed under the GPL with code licensed under the MIT License. The license's terms and conditions. It is important to read the terms and conditions of each license carefully before choosing one. Some licenses may have restrictions that you are not comfortable with.

Learn more about open-source licenses

If you are still unsure about which license to choose, you can consult an attorney specialising in open-source law.