Speaker of the House of Representatives (U.S)

The Speaker of the House of Representatives presides over the House of Representatives, the lower house of the U.S. Congress.

He or she is chosen by the sitting members of the House, as the first order of business, after each election cycle. By tradition the Speaker is a senior member of the majority party, but there is no legal requirement for them to have been elected.

The speaker is third in line to step in, and assume the powers of the Presidency, if both the President and Vice President are incapacitated.

The speaker's powers to choose who chairs Congressional committees, and to set the legislative agenda, potentially bring great power, particularly in times when the President is weak.