An "Usborne Internet-linked" book contains descriptions of Web site specially chosen to take readers further into the subject in a fun and informative way; links are found on the "Usborne Quicklinks Web site" at the end of this cataloguing record. -- Discover amazing facts about sharks of all shapes and sizes, what triggers their hunger and aggression, how they look when about to attack, and how they are able to "sense" other fish or nearby marine life.