Bells sound. Lighted messages appear. Men and women work at computers. They talk on the telephone. At times they shout and run around.

This noisy place is a stock exchange. Here expert salespeople called brokers buy and sell shares of companies. The shares are known as stocks. People who own stock in a company, own part of that company.

People pay brokers to buy and sell stocks for them. If a company earns money, its stock increases in value. If the company does not earn money, the stock decreases in value.

Brokers and investors carefully watch for any changes on the Big Board. That is the name given to a list of stocks sold on the New York Stock Exchange.

The first written use of the word with that meaning was in a newspaper in Illinois in eighteen thirty-seven. It said: "The sales on the board were one thousand seven hundred dollars in American gold."

Investors and brokers watch the Big Board to see if the stock market is a bull market or a bear market. In a bear market, prices go down. In a bull market, prices go up.

Investors in a bear market promise to sell a stock in the future at a set price. But the investor does not own the stock yet. He or she waits to buy it when the price drops.

The meaning of a bear market is thought to come from an old story about a man who sold the skin of a bear before he caught the bear. An English dictionary of the sixteen hundreds said, "To sell a bear is to sell what one has not."

Word experts dispute the beginnings of the word bull in the stock market. But some say it came from the long connection of the two animals -- bulls and bears -- in sports that were popular years ago in England.

Investors are always concerned about the possibility of a company failing. In the modern world, a company that does not earn enough profit is said to go belly up. A company that goes belly up dies like a fish. Fish turn over on their backs when they die. So they are stomach, or belly, up.

Stock market investors do not want that to happen to a company. They want a company whose stock they own to earn more profit than expected. This would sharply increase the value of the stock. Investors are hoping for a windfall.

The word windfall comes from England of centuries ago. There, poor people were banned from cutting trees in forests owned by rich land owners. But, if the wind blew down a tree, a poor person could take the wood for fuel. So a windfall is something wonderful that happens unexpectedly.

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