This lets you create a stroke pressure curve, which is a visual representation of the pressure values along the stroke. For more information, see Modify stroke pressure values interactively.
When you have finished editing with a pressure curve it is a good idea to delete it. Pressure curves have an associated expression and this should also be deleted. You can find the expression using the Expression Editor and listing expressions by name. It is safest to delete the expression before deleting the pressure curve.
Paint Effects > Curve Utilities > Make Pressure Curve >
These are the options in the Make Pressure Curve Options window.