Final answer:
In two-point perspective, orthogonal lines converge at vanishing points to create a sense of depth and three-dimensional space in a two-dimensional drawing or painting.
Step-by-step explanation:
In two-point perspective, the lines used are the orthogonal lines that converge at the vanishing points. These lines give the illusion of depth and create a sense of three-dimensional space in a two-dimensional drawing or painting. The vertical edges of objects facing the viewer, such as the edges of a cube, are used as the starting point for these orthogonal lines.
For example, in a drawing of a building using two-point perspective, the vertical edges of the building would be the starting points for the orthogonal lines. These lines would then converge at two vanishing points on the horizon line, giving the building a realistic sense of depth.