While everyone has heard of copyright, not many know what copyleft is. Here’s all you wanted to know about the importance of copyleft but didn’t know whom to ask.
A copyright gives the creator of a creative work the exclusive right to reproduce the work for a limited period of time. So, no one can republish, perform or modify that piece of work without permission from the author. Copyrights can be given to literary, artistic, musical or even technological works like software.
A copyleft, on the other hand, is a copyright but, one whose terms allow people to freely change and distribute copies of a work. The only condition is that the same rights be granted for modified works that have been created at a subsequent stage. What this means is that when you get a ‘copylefted’ work — it could be music, art, a film or anything original — you are free to change the work, but the changed versions should also be free to use, distribute and modify.
One of the ways of sharing creative work and making it accessible to all is to put it in the public domain. However, the problem here is that someone can take that creative work, modify it and copyright the modified version, making it proprietary. So, this could defeat the purpose of putting it in the public domain.
The concept of copyleft first began in the world of information technology. An example of this is the GNU Project the aim of which is to give all users the freedom to redistribute and change GNU software. If any of them passes on the software to others with or without changes, they must also pass along the freedom to make more copies and modifications. Copyleft ensures that every user receives that freedom. In fact, the first-ever copyleft license was made by Richard Stallman and was called the GNU General Public License.
Copyleft provides an incentive for creative people to improve innovations. For example, if someone composes a tune with a copyleft policy, other musicians can make changes so that you get varied and improved versions. The same applies to any other creative piece of work. This way, innovative people can benefit the community as a whole as one of the conditions of copyleft is that upgraded versions should be made available to everyone free of charge.
The importance of copyleft lies in the fact that a large community can be tapped while developing an innovation; not just an individual or a group of individuals. The large pool of people working on a creative idea can lead to exciting and innovative new developments that will be beneficial to the world at large.
There are four main types of copyleft. A weak copyleft means licenses where not all derived works inherit the copyleft license. Such licenses are used to make software libraries.
A strong copyleft makes publishing of the source code in any use case necessary. Example of a strong copyleft is The Sybase Open Watcom License.
A full copyleft means that all parts of the work can get modified and distributed. Linux is an open source project with a full copyleft policy.
In a partial copyleft, some parts of the work are exempt. For instance, any work published on Wikipedia is guided by a copyleft policy that says any content you add or change on a Wikimedia (parent firm) site will be permanently available for public use.