Taken from gnu.org: What is Copyleft? (http://www.gnu.org/copyleft/copyleft.html)
- Copyleft is a general method for making a program free software and requiring all modified and extended versions of the program to be free software as well.
- 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.”
TakeDown.NET -> “Copyleft”