What is the difference between bull's eye light and spot light?

Bull's-eye lamp, we say is the ceiling light, he is through the lens to adjust the angle of light to 30 degrees or 45 degrees or 60 degrees. This is used in the top of the wall to play out the light will have a light effect. Other downlights and ceiling lights are not which is good, just different uses, different effects.

Spotlights: other and the effect of the ceiling light is the same, but the spotlight to add a bracket to combine into a ceiling light. Then why so much trouble to do spotlights, because there is a very traditional downlight is also a two-piece set, in this case, you can use the downlight to pay for the light source. Many other foreign countries also like spotlights plus brackets.