President Barack Obama delivered the State of the Union address to Congress in 2012.

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Story highlights

Obama is only African-American to address joint session or joint meeting of Congress

The first high-definition TV broadcast of the State of the Union was in 2004

First televised State of the Union was Harry Truman's 1947 address

George Washington's 1790 address is believed to have lasted less than 10 minutes

On Tuesday, President Barack Obama will present his fourth State of the Union address, the 224th in the nation’s history. However, this will be only the 80th time a president has delivered the speech before Congress – earlier presidents routinely delivered a written message to be read to Congress.

Here are some firsts from past State of the Union addresses:

First African-American: Obama is the only African-American to have addressed a joint session or joint meeting of Congress. Over the years, several black speakers from other countries have addressed a joint meeting of Congress. Notable examples are Nelson Mandela in 1990 and 1994 and Liberian President Ellen Johnson Sirleaf in 2006.

By the Numbers: State of the Union

Records: Although Woodrow Wilson holds the record for most speeches delivered before Congress with 26, Franklin Roosevelt holds the record for the most State of the Union/annual message addresses with 12. Ten were in person, and two were in writing – one of those he read over the radio from the White House as a “fireside chat.”

Speechless: Two presidents never prepared any type of State of the Union or annual message: William Henry Harrison and James Garfield. Harrison died after only 32 days in office; Garfield after only 199 days.

On the radio: The first of the annual messages broadcast nationally on radio was Calvin Coolidge’s speech on December 6, 1923. A year earlier, Warren Harding’s annual message was broadcast on radio to a very limited audience, including the first lady, who listened from the White House while recovering from an illness.

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On TV: The first televised State of the Union was delivered by Harry Truman on January 6, 1947.

Prime time: The first prime-time State of the Union was delivered on January 4, 1965, when Lyndon Johnson moved the speech from its traditional midday time slot to the evening to attract a larger television audience.

Online: The first State of the Union to be webcast live on the Internet was George W. Bush’s 2002 address.

High-def: The first high-definition TV State of the Union broadcast was Bush’s 2004 address.

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Postponed: The first and only postponement of a State of the Union occurred in 1986. Ronald Reagan was scheduled to deliver his address on January 28, 1986 – the same day the Space Shuttle Challenger exploded. Reagan instead addressed the nation from the Oval Office that night on the tragedy and the State of the Union was delayed a week.

The longest: Bill Clinton’s 2000 address, which clocked in at 1 hour, 28 minutes and 49 seconds, according to the American Presidency Project at the University of California at Santa Barbara. Written annual messages were usually very long, with Jimmy Carter, William Howard Taft and Truman submitting the longest.

The shortest: George Washington’s 1790 address was only 833 words and is believed to have lasted less than 10 minutes.

Highlights from past addresses