Here's the United States government's official website: http://www.usa.gov
The three branches of U.S. government—legislative, judicial, and executive—carry out governmental power and functions.
Daily, Americans exercise their rights secured by the Constitution. The most widely discussed and debated part of the Constitution is known as the Bill of Rights. Belinda Stutzman provides a refresher course on exactly what the first ten amendments grant each and every American citizen.
Governments around the world do not always work the same. For instance, the Government of the United Kingdom is led by the Prime Minister, who selects all the remaining Ministers. The Prime Minister and the other most senior Ministers belong to the supreme decision-making committee, known as the Cabinet. The Government Ministers are all members of Parliament, and are accountable to it. The Government is dependent on Parliament to make primary legislation, which means that in practice a government must seek re-election at least every five years.