Parabola

A conic section generated by a the intersection of a cone and a plane parallel to the cone's axis. A parabola may also be considered to be the set of points such that the distances of each point from a given point (the focus) and a given straight line (the directrix) are equal.

In [Cartesian coordinates]? a parabola has the equation y=a x² + c, with respect to some suitable coordinates.