Visual effects are the magic behind the curtain.
In filmmaking, visual effects (abbreviated VFX) are the processes by which imagery is created and/or manipulated outside the context of a live action shot. (From Wikipedia)
Creating visual effects is the art of deception, manipulation and misdirection, much like the art of magic. It is making something appear that is an only illusion. Visual effects can be practice or digitally created. Practical effects are done ” in camera” from something as simple as a building facade to an explosion or fire. Digital Effects can be space ships and planetary systems to set extensions and green screen composites.
Visual Effects are sometimes given a bad wrap for making movies too perfect, over the top and “CGI-looking”. The best visual effects are ones you do not notice or realize they are visual effects in the scene. Just because you can make something inside a computer doesn’t mean you should. But story telling should not be held to the limitations of the real world either. Authors do not write books based on limitations of the physical world and filmmakers should not be bound by this. Visual effects have been around since the dawn of film making. Some of the earliest VFX was using the camera to create actual magic tricks, disappearing, double exposure, ghosts and doppelgangers.