And then there's Copyright
copyright
opyright insures that the person who created something--whether a book or a piece of music--is reimbursed or otherwise credited for his or her intellectual work. If there were no copyright protection, there would be no economic incentive to create these works.

A copyright is a set of legal rights that an author has over his or her work for a limited period of time. Copyright covers everything from using images or sound files from the Web to photocopying.

Most information is protected by copyright. The exception is work that is in the "public domain, " which can be reproduced or used by anyone. However, you still must credit the author. Some examples of public domain sources:

Public Domain Sources Examples
Publications of the U.S. Government constitution U.S. laws and other publications of the Federal government, the U.S. Constitution
Copyright has been waived by the author.   Software called freeware
Works on which the copyright has expired shakespeare Works by William Shakespeare
Organizations like Creative Commons have developed a standardized way for authors and creators to share their works with others.   Many of the images on Flickr have a Creative Commons license
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