Vector data are generated from a coordinate system. Lines, or arcs, are constructed by connecting points. Polygons, which define areas, are constructed of interconnected arcs. Fortunately, or unfortunately, these somewhat tidy definitions get cloudy when the concept of attribute data is introduced. In order to gain meaningful information from these models, additional data are required.
Attributes are data attached to the spatially located points, lines, areas, and cells.
For the vector model, attributes typically describe one element's relationship to another. For raster data, a cell may contain an index value which refers to an attribute file describing that place on the ground in several ways. A whole chapter, if not a book, could be devoted to the discussion of these data models. This is beyond the scope of this document. Several sources of information exist for further study of these models.