Raster
and vector are two variants of image type. Both have their own pros and
cons and win over the other is their respective strengths as most
editors learn when they start this service.
The
selection of a particular data model, vector or raster, is dependent on
the source and type of data. Importantly the decision is based on
intended use of the data. Certain analytical procedure requires raster
data while others are better suited to vector data.