Class is respect for others. It is a deep and genuine respect for every human being, regardless of their status in life.
Class is having manners. It is always saying "thank you" and "please." It is complimenting people for any and every task that is done well.
Class is treating every other person as you want them to treat you in a similar situation.
Class never makes excuses for one's own shortcomings, but it always helps the other person to bounce back from their mistakes.
Class never brags or boasts about one's own accomplishments, and never tears down or diminishes the achievements of another person.
Class does not depend on money, status, success, or ancestry. The wealthy aristocrat may not even know the meaning of the word, yet the poorest man in town may radiate class in everything he does.
If you have class, everyone will know it and you will have self-respect. If you are without class - no matter what you accomplish, it will never have meaning.