A library for performing Bezier curve computation and, if you add in your own drawing code, drawing curves in a useful manner.
The code of the classes dealing with Bezier curves is based on the excellent work at https://pomax.github.io/bezierjs/. To learn more about the math behind Bezier curves please read https://pomax.github.io/bezierinfo/ The c# version is based on the initial work at https://github.com/xclud/Bezier. The code of System.DoubleNumerics is based on https://github.com/Weingartner/System.Numerics.DoubleVectors.
The demo project explains the methods and properties of the Bezier class, with interactive graphics to illustrate what a function does. Because what's the point of a library for manipulating Bezier curves if you can't manipulate them? You can click-drag all the points to see how the curves behave under the different functions that can act on them.