The Vice President of the United States

The Vice President of the United States is the holder of a public office created by the United States Constitution. The Vice President, together with the President of the United States, is indirectly elected by the people through the Electoral College to a four-year term. The Vice President is the first person in the presidential line of succession, ascending to the presidency upon the death, resignation, or removal of the President.

Under the Constitution, the Vice President is President of the Senate. By virtue of the Vice President's role as President of the Senate, he or she is the nominal head of the United States Senate. In that capacity, the Vice President is allowed to vote in the Senate, but only when necessary to break a tied vote. Pursuant to the Twelfth Amendment, the Vice President presides over the joint session of Congress when it convenes to count the vote of the Electoral College.

While the Vice President's only constitutionally prescribed functions, aside from presidential succession, relate to his role as President of the Senate, the office is now commonly viewed as a member of the executive branch of the federal government. The U.S. Constitution does not expressly assign the office to any one branch, causing scholars to dispute whether it belongs to the executive branch, the legislative branch, or both. The modern view of the Vice President as a member of the executive branch is due in part to the assignment of executive duties to the Vice President by either the President or Congress, though such activities are only recent historical developments.

Source: Wikipedia