What Is Copyleft?

[eick_wright 0]

Copyleft is a general method for making a program or other work free, and requiring all modified and extended versions of the program to be free as well.
The simplest way to make a program free software is to put it in the public domain, uncopyrighted. This allows people to share the program and their improvements, if they are so minded. But it also allows uncooperative people to convert the program into proprietary software. They can make changes, many or few, and distribute the result as a proprietary product. People who receive the program in that modified form do not have the freedom that the original author gave them; the middleman has stripped it away.

In the GNU project, our aim is to give all users the freedom to redistribute and change GNU software. If middlemen could strip off the freedom, we might have many users, but those users would not have freedom. So instead of putting GNU software in the public domain, we ``copyleft'' it. Copyleft says that anyone who redistributes the software, with or without changes, must pass along the freedom to further copy and change it. Copyleft guarantees that every user has freedom.

Copyleft also provides an incentive for other programmers to add to free software. Important free programs such as the GNU C++ compiler exist only because of this.

Copyleft also helps programmers who want to contribute improvements to free software get permission to do that. These programmers often work for companies or universities that would do almost anything to get more money. A programmer may want to contribute her changes to the community, but her employer may want to turn the changes into a proprietary software product.

When we explain to the employer that it is illegal to distribute the improved version except as free software, the employer usually decides to release it as free software rather than throw it away.

To copyleft a program, we first state that it is copyrighted; then we add distribution terms, which are a legal instrument that gives everyone the rights to use, modify, and redistribute the program's code or any program derived from it but only if the distribution terms are unchanged. Thus, the code and the freedoms become legally inseparable.

Proprietary software developers use copyright to take away the users' freedom; we use copyright to guarantee their freedom. That's why we reverse the name, changing ``copyright'' into ``copyleft.''

Copyleft is a general concept; there are many ways to fill in the details. In the GNU Project, the specific distribution terms that we use are contained in the GNU General Public License (available in HTML, text, and Texinfo format). The GNU General Public License is often called the GNU GPL for short. There is also a Frequently Asked Questions page about the GNU GPL. You can also read about why the FSF gets copyright assignments from contributors.

An alternate form of copyleft, the GNU Lesser General Public License (LGPL) (available in HTML, text, and Texinfo format), applies to a few (but not all) GNU libraries. This license was formerly called the Library GPL, but we changed the name, because the old name encouraged developers to use this license more often than it should be used.

Notice from BuffaloHELP:

Speaking of copyrights and copyleft, when pasting from another source you must use QUOTE bbcode.

[sxyloverboy 0]

Dude, read the readme before you start posting. you should not just copy and paste text from diffrent sites and put it here. And if you really want to do it you MUST put them in quote tags.

http://www.gnu.org/copyleft/

[unicornrose 0]

GNU is one of the best known places to get programs that you can work with. My whole system is GNU. I am using Debian GNU/Linux. Its freely available and I am allowed to make as many changes as I want and I can futz around with the software if I want. When I decided I had enough with windows that is what attracted me to Linux. Number one is free and number two is freedom. Sure Linux very occationally freezes and crashes but its not every single day every couple of hours like the windows system. For me its much more stable. Plus if I am ever going to get windows again its going to be XP. At this time I can not afford to buy new software. But even so I do have a second hard drive with windows on it so that if I want to play any of my windows games or if I have to work with software that I can only use in windows its there. I am using Windows Me which is buggy as heck. So I really try not to use my windows drive all that often. I spend more time rebooting than anything else when working with it. I would much rather spend hours on my computer without rebooking and getting frustrated.

[DaeFenris 0]

Oooh, I've heard the term copyleft used somewhere (can't remember where at the moment) and I always thought it was just coined for that particular discussion.Never knew that is was defined as so. Very interesting.

[anish 0]

what more can we do fromcopy left i did not have much ideas about itplz tell me frensplz.................

Notice from jlhaslip:

The best way to answer your question is to ask that you follow the linlk to the gnu.org site.

[Munde 0]

Wauw, I honestly thought you were kidding me. I mean, what is the opposite of copyright? Copyleft! That is such an awesome term, but I'll have to save the quote, cause people won't believe me when i say it actually exists! Nice!

[Blue Lightning 0]

I have never heard of the term copyleft before.Funny how they came up with the name for it (not really.....)

[leeleelee 0]

My brother as a movie maker has copyleft on his website. I always thought he was just being funny.

[hellmet 0]

Same here..never knew that term existed...Anyways..LINUX rules for that very fact.I've used windows since childhood and I recentlymoved completely to Ubuntu..Yaa its a bit diff. at first...

[FLaKes 0]

At first I thought it was a Joke, but then I read on and found out it was just a way of defining something free in the public domain. I am dying to try Linux, and I will, whenever I have some free time. The only Linux I have ever used was Debian with a horrible GUI. Ive seen some Gentoo screenshots though, they look awesome.

[Uentil 0]

Nice, ive never even heard that word. But ya, if everyone coppy pasted off of sites, that would be too easy of credits and its not your knowledge.

[alucart13 0]

Notice from BuffaloHELP:

Speaking of copyrights and copyleft, when pasting from another source you must use QUOTE bbcode.

maybe some people just dont know a lot about copyrights. like for instance, i had no idea what a copyleft was, i thought someone just made up the word as a sort of making fun of copyright, but you know, you do learn things from these forums

[Uentil 0]

Haha.. Thats kinda funny, i like the name...

[Gyad 0]

Isn't copyleft-ing just the same as making something Freeware or Shareware? As far as I know, if you make it freeware/shareware, you're allowed to redistribute the program or software.

[icemarle 0]

Like some others here, I didn't know this beforehand... I never thought there was such a word til now... I was of course, thinking that the "right" in copyright meant the word "right" which is used in a context like "The right to freedom." Who knew they would coin a term using "left" making it the opposite to copyright? I certainly didn't expect it. ; Still pretty interesting to know, though. Thanks for digging this up.