What is Creative Commons?
The Creative Commons (CC) enables copyright holders to grant some or all of their rights to the public while retaining others through a variety of licensing and contract schemes. astrobiology prefers the Creative Commons 3.0 license, which is well suited to education and academic research. This license allows people to use your work for non-commercial purposes, but they must attribute you as a source, and they must share any derivative works under the same license.
Offering your work under a CC license does not mean giving up your copyright. It means offering some of your rights to any member of the public but only on certain conditions. You may offer your work on astrobiology under a non-commercial license and still grant commercial licenses separately, on a case-by-case basis.
For further information on Creative Commons visit the Creative Commons homepage.
From the Creative Commons FAQ:
What if I change my mind?
Creative Commons licenses are non-revocable. This means that you cannot stop someone, who has obtained your work under a Creative Commons license, from using the work according to that license. You can stop distributing your work under a Creative Commons license at any time you wish; but this will not withdraw any copies of your work that already exist under a Creative Commons license from circulation, be they verbatim copies, copies included in collective works and/or adaptations of your work. So you need to think carefully when choosing a Creative Commons license to make sure that you are happy for people to be using your work consistent with the terms of the license, even if you later stop distributing your work.
Do Creative Commons licenses affect fair use, fair dealing or other exceptions to copyright?
No. All jurisdictions allow some uses of copyrighted material without permission, such as quotation, current-affairs reporting, or parody, although these vary from country to country. These are not dependent on the license and so cannot be affected by it. To make this clear, all of our licenses include this or similar language: Nothing in this license is intended to reduce, limit, or restrict any rights arising from fair use, first sale or other limitations on the exclusive rights of the copyright owner under copyright law or other applicable laws. Thus, regardless of the jurisdiction a user is in, our licenses do not affect a user's right to use or allow use of content under copyright exceptions.
What happens if someone misuses my Creative Commons-licensed work?
A Creative Commons license terminates automatically if someone uses your work contrary to the license terms. This means that, if a person uses your work under a Creative Commons license and they, for example, fail to attribute your work in the manner you specified, then they no longer have the right to continue to use your work. This only applies in relation to the person in breach of the license; it does not apply generally to the other people who use your work under a Creative Commons license and comply with its terms.