電影或電視演出所採用之人工視覺或機械效果。最早的特效是透過特殊的攝影鏡頭，或如在演員身後投影一個會動背景的戲法所創造出來。而隨着可結合分開影片片段並取代部分影像之光學印像機的發展，特效也因此具有較大的靈活度，因而允許如讓角色飛過天際的效果。透過使用如鋼絲、爆炸物及玩偶等裝置，以及藉由建造模擬如小規模戰役的壯麗場景，特效也可以機械地在舞台上被創作出來。使用電腦繪圖及電腦產生影像的增加，已經可創作出越來越好的精巧真實地視覺效果。雖然以往每一個電影製片場都有其自己的特效部門，但是特效現在已經藉由如喬治盧卡斯之光影魔幻產業（Industrial Light and Magic）的個人公司來創造，以提供在《星際大戰》（Star War, 1977）及往後的電影中所見的革命性特效。
special effects
Artificial visual or mechanical effects introduced into a movie or television show. The earliest special effects were created through special camera lenses or through tricks such as projecting a moving background behind the actors. Greater flexibility came with the development of the optical printer, which made it possible to combine separate pieces of film and replace part of an image, thus allowing for such effects as characters flying through the air. Special effects have also been created mechanically on the set through the use of devices such as wires, explosives, and puppets and by building models to simulate epic scenes such as battles in miniature. The growing use of computer animation and computer-generated imagery has produced increasingly elaborate and realistic visual effects. Though each movie studio formerly had its own special-effects department, effects are now created by private companies such as George Lucas's Industrial Light and Magic, formed to provide the revolutionary effects seen in Star Wars (1977) and later movies.
