The point-vector representation for line segments offers several advantages over other more familiar representations for lines and 1 line segments, such as the point-slope form, the slope-intercept form and the two-point form. With the point-vector form, line segment intersection routines and related cartographic computations, such as point-in-polygon routines and detection of near-intersections, can be streamlined, simplified, and more easily understood geometrically. The point-vector segment representation retains information on the line segment and not just the line. Special case handling for vertical lines is not necessary as with some other representations; and several computational shortcuts can be derived directly from the segment end-point coordinates.