Border structure, 123, 212, 223, 224, 224, 234-235, 235, 238 BackPen, 234 Count, 234 data organization, 237 definition, 234 DrawMode, 234 FrontPen, 234, 237 LeftEdge, 234, 235, 238, 238 NextBorder, 235, 238 TopEdge, 234, 235, 238, 238 XY 234, 235, 237-238