Use the following options to set what happens when you select Surfaces > Square.
Sets the type of surface tangency created.
Fixed Boundary does not ensure continuity at the surface curves.
Tangent builds a smooth, continuous surface from the selected surface curves. When Tangent is on, the Curve Fit Checkpoints option becomes available. It specifies how accurately the Square surface will be built.
Implied Tangent creates a surface tangency based on the normal of the plane where the selected curve resides.
Sets how many isoparms are used to achieve continuity across the surface curve. Larger values might create continuity with more precision, but the surfaces might be less useful. This is especially likely when the surface curves intersect acutely.
Global tolerance means the Positional value you set in the Preferences window is used. Positional tolerance sets how close the end points need to be in order to be considered coincident.
Local tolerance lets can enter a new value to override the Positional tolerance value you set in Preferences.
Rebuild provides an option to rebuild the surface curves used to generate the Square surface. This can improve curve parameterization in some cases.
Specifies the type of geometry created. (Subdiv means subdivision surfaces.)