Black absorbs all wavelengths.
An object that appears black absorbs all wavelengths of light and reflects none.
Okay, so how can something like a billiard ball be black AND shiny?
A black object can have a shiny surface. Most of the light will be absorbed, because of the black color, but some will be reflected specularly by the smooth surface.
Fun fact: Our eyes distinguish about 2 million different colors — taking into account different hues, at different levels of brightness, and at different levels of saturation. (Saturation is related to how much white is in a color — red is more saturated than pink.)