Final answer:
A joint session of Congress is typically held for the annual State of the Union address, special sessions called by the President to address urgent issues, and for the passage of joint resolutions, which require presidential approval to become law.
Step-by-step explanation:
There are several common reasons for a joint session of Congress to be held. The most well-known is the State of the Union address, which is a yearly event where the President reports on the condition of the nation and lays out their legislative agenda. It is a requirement under Section 3 of the Constitution. However, there are other reasons for a joint session as well.
Congress may be summoned into a special session by the President to address urgent matters such as economic crises, national emergencies, or other significant issues. There is also a legislative process wherein Congress may pass joint resolutions under special circumstances, which, unlike regular bills, must be signed by the President to become law. This allows Congress to act with the same force as a law without following the usual legislative process, which is of particular use during crises or when swift action is needed.