Vector Line Illustrations
Vector graphics are drawings so when you vectorize a photograph it will be changed into a drawing. If you are looking for more realistic drawings, please see photographs traced as vector. Also see Black and White line art.
The three samples below are for the purpose of seeing the difference between a continuous tone image like a photograph (left) and a vector drawing.
As you can see on the samples above, the photographs on the left have a multitude of colors and varying shades that seem to blend colors together. The vector line illustrations on the right have clear distinction between each color.
Vector programs do have the ability to create gradients, soft color blends like shadows and highlights but this is accomplished by using raster/bitmap effects within the vector program. Images with raster effects are not considered 100% vector art. 100% vector line art is required for processes that are guided by the vector outline such as engravers and certain types of signage.