Splines Polynomial interpolation was developed in the 17 th Century, mainly to interpolate smooth astronomical data.
Splines are a more robust method of interpolation.
They were developed in the early 1960's to help in the computer aided manufacture of car bodies. They are also important in computer graphics. They are much more robust than polynomials and produce better results if the data contains sudden changes or experimental error. Such functions are called piecewise cubics. Thus when we draw the graph of a spline it will look pleasingly smooth.