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zlib License facts for kids
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| Author | Jean-loup Gailly and Mark Adler |
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| Version | 1.2.11 |
| Copyright | Jean-loup Gailly and Mark Adler |
| Published | 15 April 1995 |
| DFSG compatible | Yes |
| Free software | Yes |
| OSI approved | Yes |
| GPL compatible | Yes |
| Copyleft | No |
| Linking from code with a different license | Yes |
The zlib license is like a set of rules for using and sharing a special computer program called the zlib library. This library helps computers compress (make smaller) and decompress (make normal size again) data. Many other open-source programs also use this license.
Another similar set of rules is the libpng license, which is used by the libpng library. Sometimes, people call them the zlib/libpng license because they are so much alike.
The zlib license is approved by big groups like the Free Software Foundation (FSF) and the Open Source Initiative (OSI). This means it's considered a good license for free software and open source projects. It also works well with another popular license called the GNU General Public License.
Contents
What is the zlib License?
A software license is like a rulebook that tells you how you can use, share, or change a computer program. The zlib license is a special kind of rulebook. It's known as a permissive license. This means it gives people a lot of freedom to use the software.
The zlib license was created by Jean-Loup Gailly and Mark Adler. They released it on April 15, 1995. Since then, it has become very popular. Many different software projects use it.
Why is it "Permissive"?
Being "permissive" means the zlib license has very few rules. You can use the software for almost any purpose. This includes making your own programs, even ones you sell. You can also change the software and share your new version. You don't usually have to share your own changes or make your new program open source. This makes it very flexible for developers.
Simple Rules of the zlib License
Even though it's very flexible, the zlib license does have a few important rules. These rules help make sure everyone knows where the original software came from.
- No Guarantees: The people who created the software are not responsible if something goes wrong when you use it. The software is provided "as is," meaning without any promises.
- Sharing Your Changes: If you change the software and share your new version, you need to follow these simple points:
- You must not pretend that you wrote the original software yourself.
- Your changed version should clearly show that it's different from the original. You can't make it look like the original software.
- You must keep the original license notice with the software. This notice tells everyone about the rules.
The license does not require you to share the source code if you only give out the finished program (binary code).
See also
In Spanish: Licencia Zlib para niños
- Comparison of free and open-source software licenses
- Software using the zlib license (category)