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Ben Bitdiddle is taking notes for 6.006 on his laptop. He has to keep up with the professor and write down all of the important points. The professor begins to draw a very complex diagram on the board, and warns the class that if they don't understand all of the details of the diagram, they will fail the next exam! Ben must be able to insert the diagram into his notes without losing any of the details, and without falling behind taking notes on the rest of the lecture.
Later, while studying for the test, Ben decides to do the assigned reading from his textbook. He wants to insert additional notes into his lecture notes on the same material, so Ben opens his notes to review them while he's studying for the testmodify them. He goes over the notes, and inserts a few new facts that he forgot when he was taking the notes originally.
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