The class Planar_map_with_intersections_2 extends the class Planar_map_2, mainly by supporting insertion functions that can handle non--monotone, intersecting (even overlapping) curves among the curves of the planar map.
Since the planar map with intersections has an additional functionality of handling non -monotone and intersecting curves it needs additional functionality of the PlanarMapTraits_2 concept. We describe the PlanarMapwithIntersectionsTraits_2 concept following in this chapter.