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The great white shark is one of the most recognisable sharks in the world. The only shark larger than a great white is the whale shark. Great white sharks have been found in each of the world's oceans. Even though they have been spotted in waters as shallow as three feet (one metre) deep, these sharks spend most of their time in deep coastal waters. One of the most noticeable features of the great white is the dorsal fin which rises out of the water when a great white swims near the surface of the  ocean. The fins on other side of the shark are called pectoral fins and they help to direct the shark closer to the surface or deeper into sea. The shark’s tail is powered by very strong muscles. It sweeps the tail side to side and can reach speeds of up to 15 miles per hour (24 kilometres per hour). White sharks have never been kept in captivity for longer than 7 months; so scientists are unsure how long they live. It is believed that their life span is almost 30 years. The great white shark is the most feared predator of the ocean, by people and by sea creatures alike!