TODAY'S HISTORY: In 1850, Los Angeles was incorporated as a city.
In 1949, 12 nations signed the North Atlantic Treaty Organization (NATO) pact.
In 1968, Martin Luther King Jr. was assassinated by James Earl Ray at a motel in Memphis, Tennessee.
In 1973, the World Trade Center was dedicated in New York City.
In 1975, Bill Gates and Paul Allen founded Microsoft in Albuquerque, New Mexico.
TODAY'S BIRTHDAYS: Tris Speaker (1888-1958), baseball player; Robert Sherwood (1896-1955), playwright; Muddy Waters (1913-1983), blues musician; Maya Angelou (1928-2014), poet/author; Anthony Perkins (1932-1992), actor; Craig T. Nelson (1944- ), actor; David E. Kelley (1956- ), TV writer/producer; Hugo Weaving (1960- ), actor; Graham Norton (1963- ), TV personality; David Cross (1964- ), actor/comedian; Robert Downey Jr. (1965- ), actor; David Blaine (1973- ), magician; Dave Mirra (1974-2016), BMX rider; Heath Ledger (1979-2008), actor.
TODAY'S FACT: The Beatles remain the only artists in history to simultaneously hold the top five positions on the Billboard Hot 100 chart, a feat the group accomplished on this day in 1964.
TODAY'S SPORTS: In 1982, Wayne Gretzky of the Edmonton Oilers finished the season with 212 points. He remains the only player in NHL history to top 200 points in a season.
TODAY'S QUOTE: "There is no greater agony than bearing an untold story inside you." -- Maya Angelou, "I Know Why the Caged Bird Sings"
TODAY'S NUMBER: 31 -- days in office for William Henry Harrison, the ninth president of the United States, who died of pneumonia on this day in 1841. Harrison was the first U.S. president to die in office, and his tenure remains the shortest in U.S. presidential history.
TODAY'S MOON: Between full moon (March 31) and last quarter moon (April 8).