A requirement in the GNU GPL software license and other "free" software licenses that anyone who redistributes the software does so under the same license and also includes the source code. The "free" means free of restrictions (see free software). The copyleft clauses were written to support the copyright laws, not to eliminate them.
Strong Vs. Weak Copyleft
A "strong copyleft" license, such as the GNU GPL license, applies to all derived works, whereas a "weak copyleft" license, such as the GNU Lesser GPL, applies only to the copylefted work, not other components in the package. See GNU General Public License and copyright.
Strong Vs. Weak Copyleft
A "strong copyleft" license, such as the GNU GPL license, applies to all derived works, whereas a "weak copyleft" license, such as the GNU Lesser GPL, applies only to the copylefted work, not other components in the package. See GNU General Public License and copyright.
 | Reproduced with permission from Computer Desktop Encyclopedia. Copyright (c) 1981-2009 The Computer Language Company Inc. All rights reserved. |
Additional Resources
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