When the human eye sees any image, it perceives it as signals, which then fall on the visual cortex of the brain through the eyes. The visual cortex then processes these signals, which results in the experience of the scene. These scenes are then compared with the concepts and objects stored in one's memory and interpreted accordingly. Similarly, when an image in digital form is fed to the computer, it perceives the image as either a raster or vector image.

Raster images (graphics) are bitmaps. A bitmap is a grid of individual pixels that together make up an image. Each pixel in a bitmap is coded with specific shades of a color. Raster graphics are used for nonlinear art images such as digital photographs and scanned images.

Vector images (graphics) are based on mathematical formulas that define geometric properties of images such as circles, polygons, lines, curves, and rectangles. Vector graphics are used to represent structured images such as line art and images with flat and uniform colors.

Let's see an example of an image (refer to Figure 7.1) and its representation in vector form (refer to Figure 7.2), and raster form (refer to Figure 7.3):

Raster image: This is made up of pixels:

Vector image: This is made up of geometric figures, circles: