## ABSTRACT

Descriptive geometry is a method of graphically solving geometry problems. It is the foundation for creating engineering drawings as we know them today. This chapter deals with some basic concepts of descriptive geometry such as the orthographic projection of straight lines and the projection of inclined and oblique planes. Basic principles are introduced to enlarge or reduce plane figures. A common problem in engineering drawing is the development of intersection curves of interpenetrating solids. This chapter exposes the reader to some techniques to overcome this problem and shows how intersections of regular solids are derived. Further, methods to develop lateral surfaces of solids are introduced. Amongst others, this topic is important for sheet metal design.