The Governor General of Canada (Fr. Gouverneur général or Gouverneure générale) is the representative in Canada of Queen Elizabeth II, who is Queen of Canada and the country's head of state. (The Prime Minister of Canada is the head of government.)
The Governor General is named by the Queen on the advice of the Prime Minister. It would cause a major constitutional crisis if the monarch did not accept such “advice”. By tradition, the post alternates between an English-Canadian and a French-Canadian. Traditions such as these have the force of law in the unwritten part of Canada's constitution. Since Canada is committed to multiculturalism and Governor Generals are expected to be fluently bilingual, the designation of English or French-Canadian is mainly a matter of perception.
Although state power rests legally with the Governor General--Parliament sits at his or her pleasure, Royal Assent is necessary for all laws passed by Parliament, and the Governor General is the commander-in-chief of the Canadian Armed Forces--real political power rests with the Prime Minister, Parliament, and the provincial governments. The Governor General's is a formal, ceremonial, and cultural office.
Current and past Governors General use the style "Right Honourable" (très honorable), like the Prime Minister. However, Governors General in office also use the style "His/Her Excellency". The Governor General's official residence is Rideau Hall; by tradition, he or she also spends several weeks a year at the Citadelle in Quebec City.
The Governor General's job is primary focused around attending state banquets and functions for visiting world leaders, and giving awards and medals at special awards ceremonies. The Governor General is the Principal Companion of the Order of Canada, and therefore the Governor General often wears the red-and-white insignia of the Order at public events.
The Queen also has representatives in each provincial government: Lieutenant Governors (lieutenants gouverneurs) who are appointed by the Governor General on the advice the Prime Minister.
Unlike in some other countries, the title of the Governor General of Canada has no hyphen.