The Senate is made up of 76 senators - 12 from each state and two from each territory. One of the key difference between Senators and Members of the House of Representatives (MHRs) is that Senators represent their entire state, whereas MHRs represent a smaller electorate within their state.
The primary role of the Senate is to protect the interests of the less populous states in Parliament by giving equal representation to all states. While our party-dominated Parliament means that this role has diminished in recent years, the Senate has now assumed a greater responsibility to make sure the government of the day is accountable.
The seats in the Senate are arranged to form a U-shape. The President sits at the open end of the U-shape, Government senators sit to the right of the President and Opposition senators sit to the left. The Leader of the Government in the Senate and the Leader of the Opposition in the Senate sit in front of their respective parties at the table in the centre of the Chamber.
Minor parties and Independents sit in the central curve of the U-shape.
Source: Parliamentary Education Office