GPL vs MIT License Explained | Generated by AI
Question: What is the GPL license, and what is the difference between GPL and MIT?
Answer:
The GPL (GNU General Public License) is one of the most well-known open-source licenses. It is a copyleft license created by Richard Stallman and the Free Software Foundation. Its main goal is to guarantee that software remains free (as in freedom) forever — users must have the rights to run, study, modify, and share the software.
The core idea of GPL is:
“If you distribute the software (or a modified version), you must also provide the source code under the same GPL license.”
This creates a “viral” or protective effect: any larger program that includes or links to GPL code usually must also be released under GPL (especially in the case of GPLv3 or when distributing binaries).
The most common versions today are GPLv2 (used by the Linux kernel) and GPLv3 (newer, with stronger patent and anti-DRM protections).
MIT License, on the other hand, is a very short and permissive license (originally from MIT). It basically says:
- You can use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the software.
- The only real requirement is to include the original copyright notice and license text in all copies or substantial portions.
Key differences between GPL and MIT:
| Aspect | GPL (copyleft) | MIT (permissive) |
|---|---|---|
| Type | Strong copyleft | Permissive |
| Can be used in closed-source / proprietary software? | No — if you distribute a program that uses GPL code, the whole program usually must be GPL (source code must be shared) | Yes — you can include it in proprietary/closed-source products |
| Modifications | If distributed, modifications must also be GPL + source code provided | No requirement to share modifications or source code |
| Requirements when distributing | Must provide source code + use GPL license | Only keep copyright & license notice |
| “Viral” effect | Yes — infects larger works | No — very friendly to commercial use |
| Length / complexity | Long and detailed (especially GPLv3) | Very short (~150–200 words) |
| Philosophy | Protect software freedom for all users forever | Maximum flexibility, “do whatever you want” |
| Popular examples | Linux kernel, Git, WordPress, MySQL | React, Vue.js, Ruby on Rails, lots of small libraries |
In simple terms:
- Choose MIT if you want your code to be used as widely as possible — even in closed-source commercial products.
- Choose GPL if you want to force derivatives to stay open source and give back changes to the community.
References:
- GNU General Public License v3.0
- MIT License
- Choose a License – GPL vs MIT comparison
- Wikipedia – GNU General Public License