Unlike raster images, a vector is not composed of separate dots (pixels). Vector graphics are composed of control points with curves in between them, defined by a mathematical formula. Vector graphics are often used for printing brochures etc., which do not require accurate transmission of all the shades of a particular colour and which can be described by curves. A great advantage of vector graphics is that the scaling of images does not affect their quality. One of the most popular vector graphics editors is Adobe Illustrator.