In technical drawings, what does the term 'hidden line' indicate?

The term 'hidden line' in technical drawings refers specifically to edges or outlines of an object that are not visible from the current viewpoint or angle of the drawing. These lines are typically represented by dashed or dotted lines to distinguish them from visible edges. The purpose of hidden lines is to provide additional information about the shape and features of an object, allowing engineers and designers to communicate complex geometries effectively.

This use of hidden lines is critical in conveying the full structure of an object in a two-dimensional representation, as it gives viewers a complete understanding of both the exterior and interior features that might be obscured in a standard view. This understanding is vital in design and manufacturing fields where accurate interpretations of technical drawings affect production and assembly processes.

While other options relate to different functions in technical drawings, they do not accurately define what 'hidden line' signifies. For instance, "visible edges of an object" pertains to clear contours seen from the perspective being drawn, whereas "centerlines for symmetry" and "guidelines for drawing" denote different line types used for other purposes, like indicating symmetry or assisting in layout but not specifically representing hidden features of the object.