These two documents are not dissociative.
They mutually complement/explain each other.
Example supplied reproduces 1/1 OriginLab 6.0.
Cheers ... Jean.

Interpolate bSpline Copy.sm (36.06 KiB) downloaded 874 time(s).
Interpolate Bezier Copy.sm (72.43 KiB) downloaded 896 time(s).