The Self-Illuminated shaders will emit light only onto themselves based on an attached alpha channel. They do not require any Lights to shine on them to emit this light. Any vertex lights or pixelThe smallest unit in a computer image. Pixel size depends on your screen resolution. Pixel lighting is calculated at every screen pixel. More info See in Glossary lights will simply add more light on top of the self-illumination.
This is mostly used for light emitting objects. For example, parts of the wall texture could be self-illuminated to simulate lights or displays. It can also be useful to light power-up objects that should always have consistent lighting throughout the game, regardless of the lights shining on it.
One Normal mapA type of Bump Map texture that allows you to add surface detail such as bumps, grooves, and scratches to a model which catch the light as if they are represented by real geometry. See in Glossary normal map with alpha channel for Illumination