From The National Coalition Against Censorship:
Copyrights are meant to encourage innovation and creative activity by protecting the product of a musician, artist, writer, or scientist’s work. A copyright is a property right in an original work that gives the holder the exclusive right to control the reproduction, distribution, and other use of the original work, including the right to make new works derived from the original. With these protections, the creator can be sure to reap the rewards of his or her own work without fear that someone else will appropriate it. Copyrights can be distinguished from trademarks in that they protect a specific piece of work, where trademarks protect a brand image.
The challenge inherent in copyright law is in achieving the proper balance between the copyright holder’s interest and others’ First Amendment freedom of expression. Because these two interests are often at odds, four key “safety valves” have been developed to help maintain this delicate balance. The “idea/expression” doctrine allows only the expression of an idea to be protected, but not the idea itself. Certain concepts, for example the theme of star-crossed lovers, are so wide-spread in society that it would be unreasonable to consider them copyrighted. In this way, no one can have a monopoly on an idea. The first-sale rule gives copyright holders only the right to the first sale of their work. Afterwards, the buyer can resell or give the work to another. The third safety valve is a limitation of the length of time a work receives protection. After a copyright’s expiration, the work enters the “public domain” and may be used by anyone. Recent amendments to the original Copyright Act, such as the 1998 Sonny Bono Copyright Term Extension Act, have extended the copyright period, generating heated debate. Critics fear that these extensions make academically and socially valuable work inaccessible to the public by delaying their entry into the public domain.
The fourth and final “safety valve” allows appropriation even before the copyright’s expiration. The fair use doctrine permits the use of copyrighted works for scholarship, journalism, criticism, or parody (only if the appropriation specifically criticizes or comments on the copyrighted work itself and not society at large). Most copyright/censorship issues arise under the fair use doctrine. To help courts distinguish between fair use and infringement, several factors are considered. They include the purpose and character of the use, the nature of the copyrighted work, the amount and substantiality of the copying or appropriation, and the effect upon the potential market or value of the copyrighted work. Although these factors appear straightforward, application of the fair use doctrine has been inconsistent and unpredictable. This uncertainty has led to a chilling effect where individuals refrain from questionable fair use of copyrighted works out of fear of being prosecuted for copyright infringement. Often, these are smaller groups or individuals who cannot afford to purchase licensing rights from a copyright holder or the litigation following infringement.
Link to the rest at The National Coalition Against Censorship