Copyright (United States)
Legal rights dictating the ownership and use of media. Copyright laws generally function by prohibiting unauthorized duplication, derivation, distribution, performance, and display of media, although they do not protect the specific concepts or facts contained within that media. However, pursuant to Copyright Law Section 107, both parodies and critical analysis are explicitly exempt from the prohibition against using copyrighted media without permission.
As an example, copyright laws prohibit the duplication character of Harry Potter, but this does not mean the use of a male wizard in other works is also prohibited, so long as there are significant differences between the two characters. A TV comedy sketch could use the name "Harry Potter" if it is unambiguously part of a parody, and a book about magic in popular culture could use an image from a Harry Potter film if it seems legitimately warranted.
The "Copyright Clause" of the United States Constitution reads as follows: "To promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries." The specific rights consistent with this clause have varied over the last two centuries as legal challenges have continually shaped the scope of copyright powers.