This part of ISO 10303 specifies the interpretation of the integrated resources to satisfy requirements for the description of geometric shapes by means of manifold surface models. The following are within the scope of this part of ISO 10303: — 3D points; — points defined in the parameter space of curves or surfaces; — 3D curves; — curves defined in the parameter space of surfaces; NOTE — Such curves are also known as pcurves or cons, which are acronyms for parametrised curve and curve on surface. — the elementary curves line, circle, ellipse, parabola, and hyperbola; — intersection curves; — polylines that consist of at least three points; — the elementary surfaces plane, cylinder, cone, torus, and sphere; — swept surfaces created by rotation or linear extrusion of a curve; — sculptured curves and surfaces; — trimming of curves and surfaces using topological entities; — composition of curves and surfaces using topological entities; — replication of curves, surfaces, and surface models; — 3D offsets of curves and surfaces; — 2-manifolds. The following are outside the scope of this part of ISO 10303: — unbounded geometry; — self-intersecting geometry; — geometry in a 2D cartesian coordinate space; — replication of points; — topology without an association to a corresponding geometric domain; — non-manifolds.