You go to a store. You see many new things. You know about them before you get to the store. How do you know? You saw these things on TV. You learned about them through advertising. People have been advertising for thousands of years. Long ago, men called "criers" walked up and down the street. They shouted about things that were being sold. Later, people met at one place. This place was a market. Some people came to sell. Other people came to buy. But only those people who were at the market knew what was being sold. When people learned about printing, things changed. Soon there were newspapers. Many people read the newspapers. They saw many ads in the papers. Later, more people saw and listened to the ads on TV. Are the people who sell to us "criers"? People have been advertising for   _  .
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