History, Evolution, and Practices of the President's State of the Union Address: Frequently Asked Questions [February 27, 2017] [open pdf - 510KB]
"The State of the Union address is a communication from the President to Congress in which the chief executive reports on the current conditions of the United States and provides policy proposals for the upcoming legislative year. The address originates from the Constitution (Article II, Section 3, Clause 1), which requires 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.' […] [T]he annual State of the Union address is usually delivered by the President at an evening joint session of Congress in January. Some Presidents, however, have chosen not to deliver a State of the Union address in the January of their departure from office, or the year they were inaugurated. Since 1981, Presidents have addressed a joint session of Congress closely following their inauguration, but not as an official 'State of the Union' address. Now broadcast and webcast to a 'prime time' national and international audience, the address serves several functions: as a report to Congress and the nation on national conditions; as a platform to announce and rally support for the President's legislative agenda for the coming year; and as a unique opportunity for the chief executive to convey a vision for the nation to Congress and the American people. […] This report takes the format of answers to frequently asked questions about the State of the Union address."
CRS Report for Congress, R44770
Federation of American Scientists: http://www.fas.org/sgp/crs/index.html