A vector map is a file containing geographical objects represented through primitive objects (such as points, lines, surfaces).
This geographical information display mode associate each geographical object with a piece of semantic information, as attributes or relations.
It also enable you to exploit data through a relational graph, for example to work out rounds optimization or geoptimization processes.
This display mode is the most commonly used in GIS, except for aerial photographs and satellite imagery. It is opposed to the raster mode.