What do visible lines on a print represent?

Visible lines on a print serve the purpose of defining the edges of a part as they appear from a specific viewpoint. These lines indicate the boundaries and outlines of a physical object, allowing someone reviewing the print to understand the shape and form of the part being represented. In technical drawings, these visible lines are essential for conveying how the part will look and how it will fit within an assembly. They help in providing clarity about the physical attributes that can be directly observed when looking at the part.

The other options do not align with the function of visible lines. For instance, hidden features are typically represented by dashed or phantom lines, not solid lines. Similarly, security details like password protection and dimensions that are not to scale do not relate to the purpose of visible lines in technical drawings. Therefore, the use of visible lines is central to accurately depicting parts in a manner that is easily interpreted by anyone working with the print.