Operation Manual

46
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 General Public License. We
use this license for certain libraries in order to permit linking those libraries into non-free
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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 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 ordinary General Public License. It also provides other free
software developers Less of an advantage over competing non-free programs. These
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For example, on rare occasions, there may be a special need to encourage the widest
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In other cases, permission to use a particular library in non-free programs enables a
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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
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and the wherewithal to run that program using a modified version of the Library.
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close attention to the difference between a “work based on the library” and a “work that
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must be combined with the library in order to run.
GNU LESSER GENERAL PUBLIC LICENSE
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND
MODIFICATION
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OPEN SOURCE LICENSES (cont.)