# Anti-conformal mapping

A continuous mapping $w=f(z)$ of a neighbourhood of a point $z_0$ of the complex $z$-plane onto a neighbourhood of a point $w_0$ of the complex $w$-plane which preserves the angles between the curves passing through $z_0$ but changes the orientation. A function $f(z)$ which produces an anti-conformal mapping is an anti-holomorphic function. See also Conformal mapping.