GNU General Public License (GPL)
The GNU General Public License (GPL) is a widely used free software license, which guarantees end users the freedom to run, study, share, and modify the software. Here's a detailed look into its history, principles, and significance:
History
- The GPL was created by Richard Stallman in 1989 for the GNU Project. Its primary goal was to ensure that software remains free and that any derivative works also remain free.
- There have been several versions of the GPL:
- Version 1 (1989) - The original GPL.
- Version 2 (1991) - Addressed some issues and added the Library GPL (LGPL).
- Version 3 (2007) - Released to address new technological and legal developments, including issues with software patents and digital rights management (DRM).
Principles
- Copyleft: This is the core principle of the GPL. It means that any software released under the GPL must remain free. Any modifications or derivatives must also be distributed under the GPL, ensuring that the software remains free for all users.
- Four Essential Freedoms:
- The freedom to run the program as you wish, for any purpose.
- The freedom to study how the program works, and change it so it does your computing as you wish.
- The freedom to redistribute copies so you can help others.
- The freedom to distribute copies of your modified versions to others.
- Source Code Availability: GPL requires that the source code of the software be made available, allowing users to inspect and modify it.
Significance
Controversies and Criticisms
- Some developers and companies criticize the GPL for being too restrictive, particularly with its copyleft provisions, which they argue can deter commercial involvement.
- The compatibility issues between different versions of the GPL and other licenses have led to complex licensing scenarios.
- There have been instances of GPL violation, leading to legal actions by the Free Software Foundation (FSF) to enforce the license.
For further reading on the GPL and its implications, consider visiting:
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