From The Art and Popular Culture Encyclopedia
Copyright is a set of exclusive rights regulating the use of a particular expression of an idea or information. At its most general, it is literally "the right to copy" an original creation. In most cases, these rights are of limited duration. The symbol for copyright is ©, and in some jurisdictions may alternatively be written as either (c) or (C).
Copyright may subsist in a wide range of creative, intellectual, or artistic forms or "works". These include poems, thesis, plays, and other literary works, movies, choreographic works (dances, ballets, etc.), musical compositions, audio recordings, paintings, drawings, sculptures, photographs, software, radio and television broadcasts of live and other performances, and, in some jurisdictions, industrial designs. Designs or industrial designs may have separate or overlapping laws applied to them in some jurisdictions. Copyright is one of the laws covered by the umbrella term intellectual property.
Copyright law covers only the form or manner in which ideas or information have been manifested, the "form of material expression". It is not designed or intended to cover the actual idea, concepts, facts, styles, or techniques which may be embodied in or represented by the copyright work. For example, the copyright which subsists in relation to a Mickey Mouse cartoon prohibits unauthorized parties from distributing copies of the cartoon or creating derivative works which copy or mimic Disney's particular anthropomorphic mouse, but does not prohibit the creation of artistic works about anthropomorphic mice in general, so long as they are sufficiently different to not be deemed imitative of the original. In some jurisdictions, copyright law provides scope for satirical or interpretive works which themselves may be copyrighted. Other laws may impose legal restrictions on reproduction or use where copyright does not - such as trademarks and patents.
Copyright laws are standardized through international conventions such as the Berne Convention in some countries and are required by international organizations such as European Union or World Trade Organization from their member states.
Copyright subsists for a variety of lengths in different jurisdictions. The length of the term can depend on several factors, including the type of work (e.g. musical composition, novel), whether the work has been published or not, and whether the work was created by an individual or a corporation. In most of the world, the default length of copyright is the life of the author plus either 50 or 70 years. In the United States, the term for most existing works is a fixed number of years after the date of creation or publication.