Computer graphics involves the creation of an artificial image by some algorithmic means.
The main areas in representational computer graphics are modeling and rendering. Modeling has to do with developing equations that describe the geometry and physics of a set of objects. Rendering translates the scene description into an image, adding shading, texturing, light sources, etc. On a more mundane level, there are a variety of computer graphics programs for plotting data. These typically produce line charts, pie charts, surface grids, etc.