Merchants were traders in ancient Greece. They owned boats or rented cargo space on other boats. Merchants, known as metrics, were often foreigners. A metric did not have the same rights as a citizen of a city-state. Shipping involved a number of risks such as pirates, shipwrecks, or the cargo going bad. Shipping also had good profit possibilities, so many took the risk.For a long period of time, it was believed that the Greeks always stayed near their shores. But recent discoveries of four Greek shipwrecks have been found in the middle of the Mediterranean Sea. The location of these wrecks suggests that more adventurous merchants did not confine themselves to the shores and may have sailed across the sea.