Lightbulb joke 灯泡笑话
（重定向自Light Bulb Joke）
A lightbulb joke is a joke that asks how many people of a certain group are needed to change, replace, or screw in a light bulb. Generally, the punch line answer highlights a stereotype of the target group. There are numerous versions of the lightbulb joke satirizing a wide range of cultures, beliefs and occupations.