早期工程师制图时，把富有弹性的细长木条（所谓样条）用压铁固定在样点上，在其他地方让它自由弯曲，然后沿木条画下曲线。成为样条曲线

三次样条插值（简称Spline插值）是通过一系列形值点的一条光滑曲线，数学上通过求解三弯矩方程组得出曲线函数组的过程。-Early engineer drawings, the flexible elongated wood (so-called spline) by the weight fixed on the sample, it is free to flex in other places, and then along the wood painted curve. Becomes a spline curve

Cubic spline interpolation (referred Spline interpolation) through a series of key points of a smooth curve, mathematically by solving the three-moment equations derived curve function group process.