special prosecutor: see independent counsel.

special effects, in motion pictures, cinematographic techniques that create illusions in the audience's minds as well as the illusions created using these techniques. Some common examples are the use of rear-screen projections, in which previously photographed material is projected behind the actors; the filming of miniature objects in such a way that they look life-size; and the use of animation techniques to create realistic looking scenes, creatures, or objects that can be combined with live action that has been filmed separately. Disaster films, horror movies, and science-fiction movies are three genres that often depend on elaborate special effects. Such effects were used dramatically in the Star Wars and Raiders of the Lost Ark series. See also motion-picture photography.

Special Drawing Rights (SDRs), type of international monetary reserve currency established (1968) by the International Monetary Fund (IMF). Created in response to worries concerning the limitations of gold and dollars as the sole means of settling international accounts, SDRs are designed to augment international liquidity by supplementing the standard reserve currencies. SDRs are assigned to the accounts of IMF members in proportion to their contributions to the fund. Each participating country agrees to accept them as exchangeable for reserve currencies in the settlement of international accounts. Deficit countries can use them to purchase stronger currencies, which then can be used to pay off balance-of-payments debts. As nations adopted the current system of floating exchange rates (1973), the value of SDRs began to be set relative to a "basket" of major currencies. In 1981 the IMF reduced the basket to five currencies (the U.S. dollar, German Deutschmark, Japanese yen, French franc, and British pound); in 1999 the Deutschmark and franc were replaced by their equivalents in the euro. All IMF accounting is done in SDRs, and commercial banks accept SDR-denominated accounts. The IMF has the exclusive right of allocating SDRs; the last such allocation was made in 1981.

Education for students (such as the physically or mentally disabled) with special needs. An early proponent of education for the blind was Valentin Haüy, who opened a school in Paris in 1784; his efforts were followed by those of Louis Braille. Attempts to educate deaf children predate Haüy, but not until Friedrich Moritz Hill (1805–74) developed an oral method of instruction did teaching to the deaf become established. The development of standardized sign languages further advanced instruction of the deaf. Scientific attempts to educate mentally retarded children began with the efforts of Jean-Marc-Gaspard Itard (1775–1838) to train a feral child known as the Wild Boy of Aveyron; Itard's work influenced such later theorists as Édouard Séguin (1812–80) and Maria Montessori. Children with motor disabilities, once considered subjects for special education, are usually integrated into the standard classroom, often by means of wheelchairs and modified desks. Children with learning disabilities and speech problems usually require specialized techniques, often on an individual basis. For children with behavioral and emotional disorders, special therapeutic and clinical services may be provided.

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or pressure group

any association of individuals or organizations, usually formally organized, that, on the basis of one or more shared concerns, attempts to influence public policy in its favour. All interest groups share a desire to affect government policy to benefit themselves or their cause. It could be a policy that exclusively benefits group members or one segment of society (e.g., government subsidies for farmers) or a policy that advances a broader public purpose (e.g., improving air quality). Interest groups are a natural outgrowth of the communities of interests that exist in all societies, from the narrowest groups such as the Japan Eraser Manufacturers Association to broader groups such as the AFL-CIO to very broad organizations such as the military in authoritarian countries. Interest groups exist at all levels of government—national, state, provincial, and local—and increasingly they have occupied an important role in international affairs.

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The belief that matter, the various forms of life, and the world were created by God out of nothing. Biblical creationists believe that the story told in Genesis of God's six-day creation of the universe and all living things is literally correct. Scientific creationists believe that a creator made all that exists, though they may not hold that the Genesis story is a literal history of that creation. Creationism became the object of renewed interest among conservative religious groups following the wide dissemination of the theory of biological evolution, first systematically propounded by Charles Darwin in On the Origin of Species (1859). In the early 20th century some U.S. states banned the teaching of evolution, leading to the Scopes Trial. In the late 20th century many creationists advocated a view known as intelligent design, which was essentially a scientifically modern version of the argument from design for the existence of God as set forth in the late 18th century by the Anglican clergyman William Paley.

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