Which term describes systems of drawings that include isometric projection and orthographic projection?

• A. Projection drawings
• B. Scale drawings
• C. Sketches
• D. Surface modelling

Answer: (A)

Projection drawings describe the system used to represent a three-dimensional object on a two-dimensional sheet by projecting its features onto different planes. Isometric projection is a type of projection that shows three faces of an object at once with equal foreshortening, giving a pseudo-3D view. Orthographic projection lays out separate views—front, top, and side—each showing the true shape and size of features as seen from that direction, with dimensions that can be measured directly. Both techniques fall under projection drawings because they convey the geometry of the object through projected images rather than through perspective. The other options don’t fit: scale drawings focus on size reduction or enlargement without conveying 3D form; sketches are informal and not standardized projections; surface modelling refers to a 3D CAD representation of shapes, not a drawing system for multiple views.