CGI is the application of computer graphics, or more specifically, computer 3D graphics to special effects in film, television programs, commercials, simulators and general simulations, and print media.
CGI was first applied in the Westworld movie, 1973. Of course the first produced picture is not as good as the movie The Avenger, Transformer, Amazing Spiderman, Batman, Hulk, Man of Steel. If you imagine how the use of CGI is too difficult, consider some photos before and after the following which might surprise you.
this is the result of CGI 😉