Multimedia :
Systems that support the interactive use of text, audio, still images, video, and graphics. Each of these elements must be converted in some way from analog form to digital form before they can be used in a computer application. Thus, the distinction of multimedia is the convergence of previously diverse systems.
From : www.tamu.edu/ode/glossary.html

Computer graphics (CG) is the field of visual computing, where one utilizes computers both to generate visual images synthetically and to integrate or alter visual and spatial information sampled from the real world.
en.wikipedia.org/wiki/Computer_graphics