The United States Congress has two chambers, one called the Senate and the other called the House of Representatives (or “House” for short) which share the responsibilities of the legislative process to create federal statutory law. They occupy opposite ends of the Capitol Building.
In practice, our political system is dominated by political parties. With rare exceptions, elections are decided between the two major parties: Democrats and Republicans. Therefore, much of U.S. politics boils down to party politics.
Typically, a political party is a political organization seeking to influence government policy by nominating its own select candidates to hold seats in political office, via the process of electoral campaigning. Parties often espouse an expressed ideology or vision, bolstered by a written platform with specific goals that form a coalition among disparate interests.