Foreshortening is the effect perspective has on objects as they tilt towards the viewer – they appear to shorten in length and the parts nearer the viewer are seen as much larger than those in the distance. A thorough understanding of foreshortening is crucial to creating three-dimensional depth on a two-dimensional sheet of paper. These illustrations show how a simple cylinder changes its shape as it turns towards the viewer. The length is vastly reduced and the end of the cylinder closest to the viewer increases in size, as it swings round. Also notice how the elliptical shape of the opening in the first view becomes a full circle in the third