Congress of the United States, the legislature of the United States of America, established under the Constitution of 1789 and separated structurally from the executive and judicial branches of government. It consists of two houses: the Senate, in which each state, regardless of its size, is represented by two senators, and the House of Representatives (see Representatives, House of), to which members are elected on the basis of population. Among the express powers of Congress as defined in the Constitution are the power to lay and collect taxes, borrow money on the credit of the United States, regulate commerce, coin money, declare war, raise and support armies, and make all laws necessary for the execution of its powers.
Although the two chambers of Congress are separate, for the most part, they have an equal role in the enactment of legislation, and there are several aspects of the business of Congress that the Senate and the House of Representatives share and that require common action. Congress must assemble at least once a year and must agree on the date for convening and adjourning. The date for convening was set in the Constitution as the first Monday in December; however, in the Twentieth Amendment to the Constitution the date was changed to January 3. The date for adjournment is voted on by the House and the Senate. Congress must also convene in a joint session to count the electoral votes for the president and vice president. Although not required by the Constitution, joint sessions are also held when the president or some visiting dignitary addresses both houses. Continue reading from Encyclopedia Britannica
Theoretically, this dualism in the bicameral system is justified as an application of the principle of checks and balances. A bicameral system is desirable, it has been argued, to avoid hasty and harsh legislation, limit democracy, and secure deliberation. Although the bicameral system remained prevalent in the 20th century, there were reactions against it. Unicameral councils or commissions came to predominate in American cities, which had often been organized along bicameral patterns in the 19th century. Widespread dissatisfaction with American state legislatures led to numerous proposals for a single-chamber system during the second decade of the 20th century, but the adoption in 1934 of a unicameral legislature by Nebraska (effective from 1937) marked the only departure from the bicameral system among the U.S. states. Continue reading from Encyclopedia Britannica
Checks and balances operate throughout the U.S. government, as each branch exercises certain powers that can be checked by the powers given to the other two branches.