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When a program is linked with a library, whether statically or using a shared library, the combination of the two is legally
speaking a combined work, a derivative of the original library. The ordinary General Public License therefore permits
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lax criteria for linking other code with the library.
We call this license the “Lesser” General Public License because it does Less to protect the user’s freedom than the
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non-free programs. These disadvantages are the reason we use the ordinary General Public License for many libraries.
However, the Lesser license provides advantages in certain special circumstances.
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by limiting the free library to free software only, so we use the Lesser General Public License.
In other cases, permission to use a particular library in non-free programs enables a greater number of people to use
a large body of free software. For example, permission to use the GNU C Library in non-free programs enables many
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Although the Lesser General Public License is Less protective of the users’ freedom, it does ensure that the user of
a program that is linked with the Library has the freedom and the wherewithal to run that program using a modifi ed
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The precise terms and conditions for copying, distribution and modifi cation follow. Pay close attention to the difference
between a “work based on the library” and a “work that uses the library”. The former contains code derived from the
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GNU LESSER GENERAL PUBLIC LICENSE
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