This document discusses orthographic projections and technical drawings. It provides examples of different types of drawings and defines key terms related to orthographic projections. Specifically, it explains that orthographic projections involve projecting different views of an object onto planes that are perpendicular to the object. The front view is projected onto the vertical plane, the top view onto the horizontal plane, and the side view onto the profile plane. It also describes the first angle and third angle methods of projection.