If you want to give people the right to share, use, and even build upon a work you’ve created, you should consider publishing it under a Creative Commons license. CC gives you flexibility (for example, you can choose to allow only non-commercial uses) and protects the people who use your work, so they don’t have to worry about copyright infringement, as long as they abide by the conditions you have specified.

 

If you’re looking for content that you can freely and legally use, there is a giant pool of CC-licensed creativity available to you. There are hundreds of millions of works — from songs and videos to scientific and academic material — available to the public for free and legal use under the terms of our copyright licenses, with more being contributed every day.

 

From http://creativecommons.org/about