curve. The center of a parabola is the contact point of the figurative straight. The center of a hyperbola lies without the curve, since the figurative straight crosses the curve. The tangents from the center to the hyperbola are called 'asymptotes'. Their contact points are the two points at infinity on the curve. See also centerpoint center of mass Chebyshev center Fixed points of isometry groups in Euclidean space References Elementary geometry