Map filters use an object named map to modify an
image: you map the image to the object. So, you can create 3D effects
by mapping your image to another previously embossed image ("Bumpmap"
Filter) or to a sphere ("Map Object" filter). You can also map a part
of the image elsewhere into the same image ("Illusion" and "Make
Seamless" filters), bend a text along a curve ("Displace" filter)...