Middle Class, What is Middle Class?

When i was a child, i always had a question in my mind. The question was "Are we rich or poor?".
I had heard many times these words that some one is rich , some one is poor, and i was in confusion whether we are rich or poor?
                    One day in the school, a boy asked me, "Are you rich? "
                                 I said," I don't know"
                                 he laughed, "Then you must be poor"
                         I said, "OK, may be you are right"
The same day i came home and asked my mother, "mummy, who are we? rich or poor?"

She replied, "we are neither rich nor poor"
                               Then i came to know about the third, the middle class, we are the middle class.
            We the middle class are always in confusion.
Rich people know about things and they can also buy that, so they are happy.

Poor people don't know about many things they don't try to buy that they are also happy.

Middle class knows about things but cant buy that, so they are sad, hahaha.