In the time of the Yellow Emperor, there were no written words. People remembered things by tying knots(打结)in ropes and carving(雕刻)shapes on stone walls.
One day, the Yellow Emperor discussed a matter with a wise man named Cang Jie. Cang took out a piece of knotted rope, but he found it was rotten (腐烂的). It was impossible for him to remember the matter clearly. Then he turned to a stone wall, but he could hardly read the shapes on it because they were carved by another person.
"The ropes will be destroyed for some unknown reasons. And the shapes can only be read by a few people, "the Yellow Emperor said to Cang. "Can you come up with something better? "
Cang thought over the problem for days and nights. One morning after a heavy snowfall, he saw the footprints of some different animals. These footprints helped him recognize what animals passed by. Cang suddenly had an idea. He drew a tiger and a bear on the snow-covered ground. But soon, he found that this took too much time. He realized that he had to make the drawings easier.
All the shapes on the stone walls came into his mind. Cang kept making all kinds of shapes on the ground. He paid attention to drawing. To show the sun, for example, he used a circle with a dot in the middle. A half circle and a vertical line(垂直线)made up the moon. And three lines that are not straight were used to show water. These symbols shone brightly in the snow.
In the end, Cang created a whole set of symbols to help people remember things. People could easily understand these symbols. Since then, they have been able to write down their own history in this way.
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