Once an old man was sitting in the park reading book "learn Java in 21days". A passer by saw him and asked "You are such an old guy, why do you bother to learn Java?" "I have heard that communication language at heaven is Java so after my death when I will be in heaven, I don't want to face communication problem." old man replied. " But how are you so sure that you will be in heaven? It could be a hell also." he asked. "Yeh, doesn't matter .... I already know COBOL" .