a solid line at the edge of a paragraph.
A margain could be drawn on any edge of a paraghraph.
A solid line that can be drawn at any edge of a paragraph is called a "border." In typesetting and graphic design, borders can be used to visually separate text or sections, enhancing readability and organization. They can be applied in various styles, widths, and colors depending on the design requirements.
Border
A separator or a horizontal line.
The answer is border.
The line that forms the edge of a figure is an edge line. Which forms the figure the has been drawn. You use this line to define a drawing or a figure.
contour line
contour line
The edge is a line - straight or curved - where two faces of the solid meet.
Its perimeter
outline
outline