This demo includes three graphical display windows.

The window "Curve: X(t)" displays the cylindrical helix X(t) = (a*cos(t), a*sin(t), bt), the point X(t0), and the unit tangent and principal normal vectors T(t0) and P(t0) with their tails at X(t0).

The window "T(t) and P(t)" displays the unit tangent and principal normal vectors T(t0) and P(t0) and the unit sphere on which their heads are constrained to lie.

The window "k(t)" displays the graph of k(t).

You can change t0 and X(t) in the control window. The control window includes a list of functions that you can use for X(t), along with parameters used to define those functions.