The real projective plane is the closed topological manifold, denoted R P^2, that is obtained by projecting the points of a plane E from a fixed point P (not on the plane), with the addition of the line at infinity. It can be described by connecting the sides of a square in the orientations illustrated above (Gardner 1971, pp. 15-17; Gray 1997, pp. 323-324).

Boy surface | complex projective plane | cross-cap | cross surface | Henneberg's minimal surface | nonorientable surface | projective plane | Roman surface