A normal model is necessary to add extra detail to a 3D model without adding extra polys, which would require more resources to render. Normal maps are good when creating objects in 3D which need to have a lot of detail, but because of the limitations of current generation consoles and PC games can not have as many high detailed objects in view at one time. Normal maps allow this extra detail without losing resources.
Here is my normal map:
A specular map defines where a model is shiny or glossy. For example, metal will be shinier than wood. The closer to white an area of a specular map is the shinier that particular area will be.
Here is my specular map:
