Conics are plane curves formed by cutting a double right circular cone with a plane. The type of conic section depends on the angle of the cutting plane to the cone's axis: a circle for perpendicular, ellipse for non-perpendicular, parabola for parallel to the edge, and hyperbola for intersecting both cones. A parabola is the set of points equidistant from a focus point and directrix line, with the vertex halfway between them. The latus rectum connects the endpoints equidistant from the focus, determining how wide the parabola opens. The four types of parabolas depend on the axis and opening direction.