2D computer graphics

The first advance in computer graphics was in the use of CRTs. There are two approaches to 2D computer graphics: vector and raster graphics. Vector graphics stores precise geometric data, topology and style such as: coordinate positions of points, the relations between points, and the color, thickness, and possible fill of the shapes. Most vector graphic systems can also use primitives of standard shapes such as circles, rectangles, etc.

Early vector-graphics displays were monochrome CRTs where the picture was drawn by the cathode ray being motivated about the screen along the required path. On a scanning display, a vector graphic image has to be transformed to a raster image to be viewed. Raster graphics is a uniform 2-dimensional grid of pixels. Each pixel has a specific value such as, for instance, brightness, color, transparency, or a combination of such values. A raster image has a finite resolution of a specific number of rows and columns. Standard computer displays shows a raster image of resolutions such as 1280 columnsx1024 rows of pixels. Today, one often combines raster and vector graphics in complex file formats.