Open Source Software
Most GNU software, including some libraries, is covered by the ordinary GNU General Public License. This license, the
GNU Lesser General Public License, applies to certain designated libraries, and is quite different from the ordinary Gen-
eral Public License. We use this license for certain libraries in order to permit linking those libraries into non-free pro-
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 such linking only if the entire combination fits its criteria of freedom. The Lesser General Public License permits
more 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 ordi-
nary General Public License. It also provides other free software developers Less of an advantage over competing non-
free programs. These disadvantages are the reason we use the ordinary General Public License for many libraries. How-
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For example, on rare occasions, there may be a special need to encourage the widest possible use of a certain library,
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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
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more people to use the whole GNU operating system, as well as its variant, the GNU/Linux operating system.
Although the Lesser General Public License is Less protective of the users' freedom, it does ensure that the user of a
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TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
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