NURBs are based on control points, the order of the curve, and a knot vector. Control points guide the shape of the geometry by specifying the location of the points of the curve. The curve's order determines the minimum number of control points that define the curve. A knot vector is a sequence of parameter values for determining the continuity along a curve's length. A knot is the location where two curve segments join and form a spline. It is represented by a parameter value.
NOTE Refer to the end of this section for code examples and screen shots that show curves and loops created with different curve order, knot vector, and control point values.