Copyleft - All Wrongs Reserved

Dr. Dobbs Journal (May 1976) carried Li-Chen Wang's Palo Alto Tiny BASIC for the Intel 8080 microprocessor. There was
the title, author's name and date with "@COPYLEFT ALL WRONGS RESERVED". Roger Rauskolb, modified and
improved Li-Chen Wang's program and this was published in the December 1976 issue of Interface Age magazine. Roger
added his name and preserved the COPYLEFT Notice.

The Emacs General Public License of Richard Stallman ws the first copyleft license which later evolved into the GNU General
Public License. The copyleft label was not yet there.

The term "kopyleft" with the notation "All Rites Reversed" was also in use in the early 1970s.

The copyleft symbol which is the “reversed c in a full circle” is copyright symbol mirrored but has no legal meaning.

Copyleft could be defined as a copyright licensing scheme in which an author surrenders some but not all rights under copyright
law. Copyleft allows an author to impose some of the copyright restrictions on those who want to engage in activities that
would otherwise be considered copyright infringement.

Copyleft expresses the practice of using copyright law to remove restrictions on distributing copies and modified versions of a
work for others and stipulates or makes a precondition/proviso that the same freedoms be preserved in modified versions.

Copyleft is a form of licensing and may be used to modify copyrights particularly for works such as computer software.
Copyleft protects the freedom of others to use copyrighted works as if there were no copyright law at all.

Copyleft licenses are also known as viral or reciprocal licenses because under copyleft, copyright infringement may be avoided
if the potential infringer perpetuates the same copyleft scheme.

An author may, through a copyleft licensing scheme, give permission to reproduce, adapt or distribute the work as long as any
resulting copies or adaptations are also bound by the same copyleft licensing scheme. A widely used and originating copyleft
license is the GNU General Public License. Other examples are licenses available through Creative Commons.

The term "copyleft" was originally a noun, meaning the copyright license terms of the GNU General Public License originated
by Richard Stallman as part of the Free Software Foundation's work.

Copyleft gives each person possessing a copy of the work the same freedoms as the author:

to use and study the work,
to copy and share the work with others,
to modify the work, and
to distribute modified and therefore derivative works.

But these freedoms do not ensure that a derivative work will be distributed under the same liberal terms. In order for the work
to be truly copyleft, the license has to ensure that the author of a derived work can only distribute such works under the same
or equivalent license.

Copyleft licenses make creative use of relevant rules and laws. By submitting the copyright of their contributions under a
copyleft license, they deliberately give up some of the rights that normally follow from copyright, including the right to be the
unique distributor of copies of the work.

Copyleft licenses vary from one country to another, and may also be granted in terms that vary from country to country. In
some countries it is acceptable to sell a software product without warranty, in standard GNU GPL style, while in most
European countries it is not permitted for a software distributor to waive all warranties regarding a sold product. The extent of
such warranties are specified in most European copyleft licenses.

Copyleft is a feature of most free software licenses. Many free software licenses are not copyleft licenses because they do not
require the licensee to distribute derivative works under the same license.

GNU's Free Documentation License allows authors to apply limitations to certain sections of their work, exempting some parts
of their creation from the full copyleft mechanism. In the case of the GFDL, these limitations include the use of invariant
sections, which may not be altered by future editors. The initial intention of the GFDL was as a device for supporting the
documentation of copylefted software. It can be used for any kind of document.

Copyleft licenses are sometimes referred to as viral copyright licenses, because any works derived from a copyleft work must
themselves be copyleft when distributed.