Mermaids are imaginary creatures that exist in legends and folk tales. They are half human and half fish and are believed to be living in deep oceans and seas. According to Greek mythology, mermaids cause the death of sailors. Some German folk tales also mention mermaids; they denote them as Rhine Maidens who live in a castle at the bottom of a river. However, how story- related mermaids came into existence is still unknown. Some say that primitive people who had never seen boats and sailors, presumed sailors to be mermen from the Deep Ocean.