Vector graphics formats store images as mathematical representations of image elements, such as shapes or lines. For example, a line segment might be defined in terms of the coordinates of its starting point, a direction, and a length. More complex shapes can be built up from simple shapes. Enclosed shapes can also be filled with colours. Some vector formats support 3-D objects as well, such as wire frame models. Vector formats are most commonly used in the field of Computer-Aided Design (CAD), since they are ideally suited to the creation of architectural and engineering drawings, maps, schematics, and charts. They also form the basis for 3-D modelling and animation, although this is beyond the scope of this Guidance Note.
Vector files can be easily manipulated, and rescaled without loss of quality. The size of a vector file is proportional to the complexity of the image (unlike raster images). Vector files do not usually support compression. However, vector file sizes are typically far smaller than the equivalent raster image