GPLv2 vs. LGPL

Attribute	GPLv2	LGPL
License Type	Strong copyleft	Weak copyleft
Derivative Works	Must be licensed under GPLv2	Can be linked with proprietary software
Compatibility	Not compatible with proprietary licenses	Compatible with proprietary licenses
Usage	Primarily for standalone applications	Primarily for libraries

Introduction

When it comes to open-source licenses, two of the most popular choices are the GNU General Public License version 2 (GPLv2) and the GNU Lesser General Public License (LGPL). Both licenses are created by the Free Software Foundation and have their own unique attributes that developers need to consider when choosing which one to use for their projects.

Scope of Application

One of the key differences between GPLv2 and LGPL is the scope of application. GPLv2 is a strong copyleft license, which means that any derivative work based on a GPLv2-licensed software must also be released under the GPLv2 license. This ensures that the software remains free and open-source. On the other hand, LGPL is a more permissive license that allows developers to link their proprietary software with LGPL-licensed libraries without having to release the proprietary code under the LGPL license.

Compatibility

Another important factor to consider when choosing between GPLv2 and LGPL is compatibility with other licenses. GPLv2 is not compatible with many proprietary licenses, as it requires that any derivative work be released under the same license. This can be a limitation for developers who want to combine GPLv2-licensed code with proprietary code. On the other hand, LGPL is more flexible and allows developers to link LGPL-licensed libraries with proprietary code without imposing the same restrictions.

Dynamic vs. Static Linking

One of the key differences between GPLv2 and LGPL is how they handle dynamic and static linking. GPLv2 considers dynamic linking to be a form of distribution, which means that any software that dynamically links to a GPLv2-licensed library must also be released under the GPLv2 license. This can be a concern for developers who want to use GPLv2-licensed libraries in their proprietary software. On the other hand, LGPL allows for dynamic linking without imposing the same restrictions, making it a more attractive option for developers who want to use LGPL-licensed libraries in their proprietary code.

Contributions and Modifications

Both GPLv2 and LGPL require that any modifications made to the original code be released under the same license. This ensures that the software remains free and open-source, and that any improvements made by the community are shared with everyone. However, LGPL is more lenient when it comes to contributions to libraries. Developers can make modifications to LGPL-licensed libraries and distribute them under a different license, as long as the original library remains under the LGPL license.

Conclusion

In conclusion, both GPLv2 and LGPL have their own unique attributes that developers need to consider when choosing a license for their projects. GPLv2 is a strong copyleft license that ensures software remains free and open-source, but it can be restrictive when it comes to compatibility with proprietary licenses and dynamic linking. On the other hand, LGPL is a more permissive license that allows for dynamic linking and is more flexible when it comes to combining open-source and proprietary code. Ultimately, the choice between GPLv2 and LGPL will depend on the specific needs and goals of the project.