About twenty years ago, there were different methods for crafting visual effects. CGI is a relatively new method compared to the other methods of visual effects. There are plenty of different methods and purposes for using visual effects. WPTV says that among the many purposes for visual effects were enhancement of the action and the environment. One example of visual effects is matte painting. A visual effects artist would paint a picture of a piece of environment or something else. The editors would combine the shot that does not have the visual effects with the matte painting in order to achieve the intended effect. This used to be done with 70MM film in order to minimize the loss of quality in the shot.
Matte painting is actually a very respected method of visual effects. However, these days the effect is achieved with the use of computers. It is not as simple as it sounds, the lighting has to match with the two shots as they are combined. Anything that is off in the shots could ruin the effect that was intended by the shot. This is why studios look to companies such as Pulse Evolution Corporation run by John Textor. These companies are experts at bringing the intended effect to life for the audience.
Among the many notable films with digital effects are Star Wars, Blade Runner, Terminator 2: Judgment Day, among other films. These films are recognized for their achievement in visual effects and are even known for changing the industry in their release.