Special effects (or SFX) are used in the film and entertainment industry to create effects that cannot be achieved by normal means, such as travel to other star systems. They are also used when creating the effect by normal means is prohibitively expensive, such as an enormous explosion. They are also used to enhance normal visual effects.

Many different visual special effects techniques exist, ranging from traditional theater effects, through classic film techniques invented in the early 20th century, to modern computer graphics techniques (CGI). Often several different techniques are used together in a single scene or shot to achieve the desired effect.

Special effects are often "invisible." That is to say that the audience is unaware that what they are seeing is a special effect. This is often the case in historical movies, where the architecture and other surroundings of previous eras is created using special effects.

Visual special effects techniques (in rough order of invention):

practical effects -
in - camera effects -
miniature effects
matte paintings -
Hitchcock zoom
optical effects
travelling matte -
bluescreen
prosthetic makeup effects
motion control photography
animatronic - models
digital compositing
wire removal
morphing
Computer Generated Imagery

Notable special effects artists:

Richard Edlund -
Ray Harryhausen
Derek Meddings -
Ken Ralston -
Douglas Trumbull -

Notable special effects companies:

Cinesite -
Computer Film Company
Digital Domain -
Industrial Light and Magic
SGI
Weta Digital

See also: computer graphics, postproduction - , stage props - , sound effects