. Curve fitting
. Interpolation : 모든 control point를 지나야 함.
control point가 많으면 noisy해짐(oscillatory feature)
Lagrange, Hermite, Cubic spline, B-spline, piece-wise method
참고) Numerical Analysis
. Approximation : 모든 control point를 지날 필요 없음.
control point가 많아도 smooth하다.