A transformation that preserves the angles between curves. A well-known example is Mercator’s projection in cartography, in which any angle between a line on the spherical surface and a line of latitude or longitude will be the same on the map. Conformal transformations are used in a number of areas in physics, particularly in dealing with electromagnetic and gravitational fields and in fluid mechanics. Problems can often be simplified by applying conformal transformations to change a complicated geometrical arrangement to a simpler one.