The 2019 State of the Union address will officially take place February 5. Here are the answers to a few questions—from when the first address occurred to the story behind the opposition's response—that might come up while you're watching.

Why does the president give a State of the Union address to Congress every year?

The State of the Union address can trace its roots back to the Constitution. Article II, Section 3, Clause 1 of the Constitution says that the president "shall from time to time give to the Congress information of the State of the Union, and recommend to their Consideration such measures as he shall judge necessary and expedient."

When was the first State of the Union address?

"From time to time" leaves the question of frequency open to interpretation, but George Washington helped cement the State of the Union as an annual event after he gave the first State of the Union address at Federal Hall in New York City in January 1790.

Since there wasn't much of a blueprint for Washington, he praised the 1st Congress's work and outlined a brief legislative plan for the upcoming year: He wanted to work on the army, build post roads, and develop uniform systems of currency, weights, and measures. In December 1790, Washington gave his second State of the Union address and firmly established it as an annual event—and the tradition that it take place near the end of the year. Until 1934, the State of the Union was usually in December or November. This would change to the beginning of the year after the 20th amendment moved the start of Congress up to January.

Has every president given an annual State of the Union address?

No. You'll notice that the order from Article II, Section 3 of the Constitution doesn't say anything about a speech; the president just has to keep Congress informed of what's going on in the country. When Thomas Jefferson took office in 1801, he decided that the idea of showing up before Congress to deliver a grand address sounded like something a monarch would do, so he decided to bag the speech. Instead, he wrote down an annual message and sent it to Congress, where a clerk read it aloud to the legislators.

Apparently presidents don't love giving long speeches any more than the rest of us do, because Jefferson's successors jumped on this new system. For over a century, every president opted to keep Congress informed through a written message rather than a spoken one; these messages were generally full of long, exhaustive administrative and budget reports rather than rousing political rhetoric. Two presidents—William Henry Harrison and James Garfield—didn’t give a State of the Union in any form due to dying early in their presidencies.

Which president brought the State of the Union address back?

Woodrow Wilson finally revived the old practice of delivering a speech in 1913. Even then, presidents haven't always appeared to give a speech. Since the 1913 revival of the practice, 19 State of the Union reports have come in written form, most recently Carter's 1981 report.

Who are all of the people crammed into the front of the House Chamber during the State of the Union address?

It's a big crowd for the State of the Union. In addition to the members of Congress, the president usually has the Justices of the Supreme Court, the Joint Chiefs of Staff, and most of his cabinet seated at the front of the audience.

Who won't be at the State of the Union address?

At least one member of the president's cabinet. Since the Cold War, one member of the cabinet has holed up in an undisclosed secure location during big government gatherings like the State of the Union address and presidential inaugurations. This absent member is dubbed the "designated survivor." In the unlikely event that an attack or a disaster leads to the deaths of all of the assembled leaders, having a designated survivor hiding out somewhere safe maintains the line of presidential succession.

Since 2005 a few members of Congress have also stayed away from big events so there would be at least a tiny legislature remaining in the event of a disaster.

When was the first televised State of the Union address?

President Truman gave the first televised State of the Union in 1947, but it didn't become a primetime spectacle until 1965. Lyndon B. Johnson decided to give his address in the evening that year, while previous addresses had generally taken place during the day. At the time, LBJ was trying to sell Americans on his civil rights reforms and Great Society plans, so he decided to give the address at night in order to reach the widest possible audience. The trick worked, and it was the first State of the Union address to be televised during the evening.

Can a president opt out of giving a State of the Union address?

Sort of. It doesn't really make a lot of sense for a newly inaugurated president to deliver a State of the Union address after only having been in office for a few days. Since Ronald Reagan's first term started in 1981, new presidents have opted to give a somewhat more specialized address—generally about the economy—to a joint session of Congress. Although these speeches are accompanied by the familiar pomp and circumstance, they're not technically State of the Union addresses.

Which president started the parade of honored guests at the State of the Union?

Could such a Hollywood flourish have come from anyone other than Ronald Reagan? His 1982 address was the first to feature personal guests that the president publicly recognized over the course of his speech. Openly gay NBA veteran Jason Collins and two survivors of the Boston Marathon bombing were among 2014's guests. In 2015, former Cuba prisoner Alan Gross and astronaut Scott Kelly attended.

Notable guests from past events include 12-year-old music prodigy Tyrone Ford (1986), baseball sluggers Sammy Sosa (1999) and Hank Aaron (2000), Baby Einstein founder Julie Aigner-Clark (2007), and NBA star Dikembe Mutombo (2007).

Why does the opposition party give a response right after the State of the Union address?

In 1966, television networks gave the Republican Party a half-hour slot for a rebuttal of LBJ's address. Senator Everett Dirksen and Representative Gerald Ford made counterarguments to Johnson's comments—five days later and very late at night. After the State of the Union moved into the evening in 1965, the audience skyrocketed and it became a much more hyped event; Republicans realized they needed their own soapbox. Since 1976, the opposition's response has been slotted in directly behind the State of the Union.

Which president gave the longest State of the Union address in history?

According to the House of Representatives, Bill Clinton takes that prize with a 1995 speech—over 9000 words (the average modern address is in the neighborhood of 5000 words). And according to UCSB’s American Presidency Project, the longest time since 1966 was Clinton’s 2000 speech at nearly an hour and a half. Jimmy Carter takes the prize for longest written address at over 33,000 words.

A version of this post originally appeared in 2010 and 2015.