An elderly man was having major problems with his computer and he was just on his last nerve.
Something happened and he didn't know how to fix the problem [been there/ lived through that,] so he thought and thought and then he knew just who he would call--his next door neighbor's son who was eleven.
This man had seen the kids' room before while visiting his parents. To him it looked like "Mission Impossible" with all kinds of gadgets, computers and every electronic device ever known to man crammed all into one room. And so the elderly man called and the kid came over.
The boy took a few minutes and fixed the computer. The man said, "What did I do wrong?" And the boy said, "It was an ID ten T problem." "Well," said the man, "How will I know when it happens again and how will I know what to do?" "It's an ID ten T problem," said the boy. "And oh by the way write it down" he added. The boy left and the man wrote it down on paper and this is how it looked: IDIOT.