1. AP US History This Day in American History November 21
1877 – The American inventor, Thomas Edison, announces his invention of the phonograph, a way to record and play back sound.

2. AP US History This Day in American History November 21
1931 – The University of Southern California surprises Notre Dame with a last-minute game-winning field goal at the new Notre Dame Stadium in South Bend. The victory won USC the national championship and was, according to that year’s Trojan yearbook, "the biggest upset since Mrs. O’Leary’s cow knocked over that lantern."

3. AP US History This Day in American History November 21
1967 – Gen. William Westmoreland, commander of U.S. Military Assistance Command Vietnam, tells U.S. news reporters: "I am absolutely certain that whereas in 1965 the enemy was winning, today he is certainly losing."

4. AP US History This Day in American History November 21
Rocky, starring Sylvester Stallone as the underdog prizefighter Rocky Balboa, debuts in New York City. The movie, which opened in theaters across the United States on December 3, 1976, was a huge box-office hit and received 10 Academy Award nominations, including Best Actor and Best Original Screenplay for the then-little known Stallone. Rocky ultimately took home three Oscars, including one for Best Picture, and made Stallone one of the biggest stars in Hollywood.