Tonight, President Obama will deliver his final State of the Union Address, an annual speech that touches on key national issues and outlines the President’s legislative agenda.

But did you know that the State of the Union wasn’t always a speech? And it wasn’t always referred to as the State of the Union. 

Impress your friends with these 12 fun facts about the history and traditions of the State of the Union.

1/ The US Constitution says nothing about when or how the State of the Union should be delivered.

It only requires the President to periodically give Congress information on the condition of the nation and recommend any measures that he believes are necessary and urgent.

2/ Back in the day, most US presidents delivered the State of the Union as a written report.

In 1913, Woodrow Wilson re-established the practice of delivering the address in person. Prior to that, the address was often written and sent to Congress because many believed the act of giving a speech was too monarchical.

3/ The first State of the Union message was given by George Washington in 1790.

It was delivered in person and was the shortest address to date. Some say it lasted only 10 minutes.

4/ Every year, the Speaker of the House formally invites the President to the State of the Union Address.

The invitation comes in the form of a letter and is sent several weeks prior to the address.

5/ During the State of the Union, one cabinet secretary remains surrounded by secret service agents somewhere else, waiting to become President if catastrophe should strike.

This “designated survivor” is selected by the White House Chief of Staff and will become the President if everyone above him or her in the presidential line of succession dies in a crisis at the House chamber.

Following the September 11 terrorist attacks in 2001, it is now tradition for a few members of Congress to relocate to undisclosed locations as well.

6/ Since the 1982 address, it has become common for the President to honor special guests sitting in the gallery.

President Ronald Reagan was the first to do this and inspired a new term in the process. His acknowledgement of Lenny Skutnik during the 1982 address has led many to refer to gallery guests as “Lenny Skutniks.”

7/ The Joint Chiefs of Staff and Supreme Court Justices rarely applaud during the address.

They do this in order to retain the appearance of political impartiality.

8/ Bill Clinton delivered the longest lasting State of the Union speech.

It was his final State of the Union and lasted about an hour and a half.

9/ During the 2011 address, all members of Congress sat together regardless of party and avoided standing while applauding.

This was in response to the 2011 Tucson Shooting in which Representative Gabrielle Giffords was shot and wounded in an assassination attempt.

10/ The longest applause interruption during an address clocked in at 52 seconds.

This was in 2007, when President George Bush honored Staff Sgt. Daniel Clay, who was killed while serving in Iraq.

11/ Congress members camp out all day to get an aisle seat at the State of the Union.

Because who doesn’t want to shake the President’s hand and be seen on TV?

12/ Most State of the Union speeches go through at least 20 drafts.

There's a reason the State of the Union Address captivates audiences worldwide. 

There you have it.

Tune in tonight at 9:00 PM ET to see if President Obama can break Bill Clinton’s record for longest State of the Union Address! 

And click here to read more about this year's carefully selected Lenny Sputniks.