How is the presiding officer in each house chosen?

THe House Speaker and the Senate majority leader are elected from the majority party. The Senate also has a president pro tempore who is elected by the Senate and now is traditionally the majority senator with the most seniority. The Vice President of the United States is the president of the Senate, but can not vote except in the case of a tie. The vice president is elected by the elecoral college along with the President.