This image of social class is from Henslin's A Down To Earth Approach and available here. The ladder shows one model for how sociologists view class in the United States. This model is not set in stone it is fluid and dynamic. People do not necessarily fit neatly into each class, but the model gives us a sense of how the US is divided by class. And the model shows that there is more to class than income/money. It is also about wealth, power, prestige, education among other things as illustrated in my other post.
