From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Visual_effects

Visual effects (sometimes abbreviated VFX) is the process by which imagery is created or manipulated outside the context of a live-action shot in filmmaking and video production. The integration of live action footage and other live action footage or CGI elements to create realistic imagery is called VFX.

VFX involves the integration of live-action footage (which may include in-camera special effects) and generated-imagery (digital or optics, animals or creatures) which look realistic, but would be dangerous, expensive, impractical, time-consuming or impossible to capture on film. Visual effects using computer-generated imagery (CGI) have more recently become accessible to the independent filmmaker with the introduction of affordable and relatively easy-to-use animation and compositing software.

History of effects (special and visual)