Dr. Martin Luther King Jr. acknowledging the crowd at the Lincoln Memorial for his "I Have a Dream" speech during the March on Washington on Aug. 28, 1963. Monday, Jan. 17, 2011, marks the 25th federal observance of the birth of King, one of America's most celebrated citizens, and the only non-US president to be honored with a national holiday.
Monday is Martin Luther King Day, a federal holiday. It honors the slain civil rights leader. How much do you know about him? Here are 10 questions.