XY direction controls the angle, through a circle that the light is shone. Left, right, top bottom or settings in between. Ambient Intensity is much like a brightness control. Diffuse Color colors the light that is shinning on the text. Diffuse Intensity controls the amount of light contrast between the shadow and highlight areas of the text.
Shininess controls the amount of shininess of the text.
Highlight Color colorers the highlights of the text. Highlight Intensity controls the amount of color added to the highlight of the text. Reflection Mapping - create the look of wet, shiny, or metallic objects, and other effects. It wraps the reflection map around your image. This can be used to create the look of wet, shiny, or metallic objects.