We're familiar with representing solids in perspective drawings.[br]Drag the slider to the right. Now you see the prism represented in a totally different way: as a planar graph. Planar graphs focus on other aspects of solids than perspective drawings.[br]Planar graphs lack scale, distance and shape, but the sides don't cross each other and the relationship between points is maintained.[br]In the planar graph of the prism we can easily see that a prism has got 9 sides and 6 vertices. And more: each vertex is directly connected to 3 other vertices by a side.