Portfolio

Logo Design
Special Effects
Web/GUI Design
         Sales/Corporate presentations
       CD-ROM Games
    Video Graphics
      Medical/Scientific Visualizations
       Architectural Walk Throughs
          Products/Mechanical
             2D/3D Animations
                         Drawings/Paintings

This is not a complete list of all graphic categories
(just the ones I have had chance to create for)
Each section above requires a different skills set, & some require different graphics software. However Design principles usually stay the same. A designer is usually really good at few of the above categories.