Texture Type that gives Glossines

So im trying to work out what type of texture that gives an object its glossiness is it diffuse or specularity if it is specularity shoul i used it in my game cause im trying to make game with decent graphics but also playable on low spec pcs

The color map is the diffuse map and the specular map is how shiny a material is intended to be. Shaders use the specular map to create the intended effects. Other properties might also include the hardness and reflectiveness as well as the transparency of the material, especially if you want glass effects such as windows. The final effect is a combination of the material, the various maps such as diffuse, normal and specular, and the use of shaders within the engine.