Based on my income, I would probably classified as middle class here in America. In reality, I have consumer debt from poor financial decisions and my net worth is below zero, however its not something I have trouble paying monthly and it will be payed off in a few years. Like others I realize that compared to the rest of the world, I am doing pretty good. I think the necessities are food, clothing and shelter. Everything else is extra. I can just look around myself as I sit at this computer and I see a lot of extras.
I live in an apartment that is about 950 square feet, a small amount of living space by US standards and the fact that I live in an apartment is considered a trait of someone with not much money. Yet its more space than is necessary for sheltering two married people. Just the fact that I can access the Internet is an extra resource that isn't available to most people in the world. So I'm not complaining at all.