The United States Senate is a chamber of the bicameral United States Congress; it is the upper house, and the U.S. House of Representatives is the lower house. Together, the Senate and House have the authority under Article One of the U.S. Constitution to make and pass or defeat federal legislation.
The Senate has exclusive power to confirm U.S. presidential appointments, to approve or reject treaties, and to convict or exonerate impeachment cases brought by the House. The Senate and the House provide a check and balance on the powers of the executive and judicial branches of government. The composition and powers of the Senate are established by Article One of the U.S. Constitution, which has been in effect since March 4, 1789. Each of the 50 states is represented by two senators who serve staggered six-year terms, for a total of 100 members.