Simplify the following text for a Grade 9 native English-speaking person.
Original: Robert James `` Bobby '' Fischer ( March 9 , 1943 â `` January 17 , 2008 ) was an American-born chess Grandmaster and the eleventh World Chess Champion .
Simplified: Robert James `` Bobby '' Fischer ( March 9 , 1943 â `` January 17 , 2008 ) was an American chess player and the eleventh World Chess Champion .