Jealousy is an emotion and typically refers to the negative thoughts and feelings of insecurity, fear, and anxiety over an anticipated loss of something that the person values, such as a relationship, friendship, or love. Jealousy is an experience in human relationships. It has even been observed in infants that are five months old and older. Some claim that jealousy is seen in every culture. However, others claim jealousy is a culture-specific phenomenon.
Many things can happen when a person becomes jealous. A person may become depressed and sad. This may even cause the person to hurt themselves or just be depressed for a long period of time. A person may also become angry. When a person is angry they might hurt someone or do something to harm the other person.
Jealousy can take many forms. A person may be sad, or angry because they are envious of another person. Everyone will feel the emotion of jealousy in thier lifetime and there is no avoiding it. It is a very strong emotion and it can cause people to do things that they don't mean. Jealousy has also been a theme of many novels, songs, poems, films and other artistic works. (http://www.tipsforsuccess.org/jealousy.htm)