President of the Senate (Australia)
The position is provided for by Section 17 of the Constitution of Australia. The Senate elects one of its members as president at the start of each new term, or whenever the position is vacant. This is usually—though not necessarily—a member of the party or coalition that holds the most seats in the Senate. The largest party in the Senate is not always the governing party, as government is determined by the House of Representatives. The President of the Senate and the Speaker of the House of Representatives may consequently be from different parties.
Parliament of Australia
The Parliament of Australia (also known as the Commonwealth Parliament or just Parliament) is the legislative branch of the government of Australia. It consists of three elements: the Crown (represented by the Governor-General), the Senate and the House of Representatives. The combination of two elected chambers, in which the members of the Senate represent the states and territories while the members of the House represent electoral divisions according to population, is modelled on the United States Congress. Through both chambers, however, there is a fused executive, drawn from the Westminster System.