When the American Revolution ended in 1783, the United States Government was in a state of flux. The founding fathers (George Washington, Thomas Jefferson, Benjamin Franklin, John Adams, Alexander Hamilton, John Jay, and James Madison) did not want to establish another country that was ruled by a king. The discussions were centered on having a strong and fair national government that protected individual freedoms and rights and did not abuse its power. When the new Constitution was adopted in 1787, the structure of the infant government of the United States called for three separate branches of government, each with their powers and systems of checks and balances. This would ensure that no one branch would become too powerful because the other branches would always be able to check the power of the other two. 

The legislative branch is described in Article 1 of the US constitution. It has 100 US senators (two for each state), and 435 members in the House of Representatives, which is better known as the US Congress. Making laws is the primary function of the US Congress, but it is also responsible for approving federal judges, US Supreme Court justices, passing the national budget and declaration of war.

The executive branch is described in Article 2 of the US Constitution. The leaders of this branch of government are the President and the Vice President. They are responsible for enforcing the laws the Congress sets forth. The President works closely with a group of advisors known as the Cabinet. They assist the President in making important decisions within their areas of expertise, like defense, the treasury and homeland security. The executive branch also appoints government officials, commands the armed forces, and meets with leaders of other nations. 

The third branch of the US government is the judiciary and is detailed in Article 3. This branch comprises all the courts in the land, from the federal district courts to the US Supreme Court. These courts interpret the nation's law and punish the ones who break them. The Supreme Court settles disputes amongst states, hears appeals from states and federal courts and determines if federal regulations are constitutional. 

Separation of powers in the United States is the backbone of the Checks and Balances System which provides each branch of the government with special powers to check the other branches and prevent any branch from becoming too powerful. Congress has the power to make laws; the President has the power to veto them, and the Supreme Court may declare the laws as unconstitutional. If both the houses of the Congress have a ⅔ majority, they can override the President's veto. The idea of checks and balances is that it is not enough to separate the powers and guarantee the independence of three branches but also that each branch needs to have the constitutional means to protect the system in case of overreach by any other branch. 

 The Check and Balances system also provides the branches with special powers to appoint or remove members from other branches. Congress (Senate and House of Representatives) can impeach or convict the President of high crimes like bribery or treason. The House of Representatives has the power to bring impeachment charges against the President, and the Senate can convict and remove the President from office. Supreme Court candidates are appointed by the President and confirmed by the Senate. Judges can also be removed by impeachment in the House of Representatives and conviction in the Senate. 

The legislative branch, which consists of the Senate and House of Representatives, passes bills, controls the federal budget, and has the power to borrow money on credit on behalf of the United States. It also has the sole authority to declare war, as well as to raise and regulate the military. It oversees, investigates and makes rules for the government and its officers. The Senate can ratify treaties signed by the President and give advice and consent to presidential appointments to the federal judiciary, federal executive departments and other posts. It also has the sole power of impeachment (House of Representatives) and trials of impeachment (Senate). 

The executive branch consists of the President and the Cabinet. The President is the commander-in-chief of the armed forces, executes the instructions of the Congress, may veto bills passed by Congress (but the veto may be overridden by a two-thirds majority of both houses), perform the spending authorized by the Congress, declare emergencies and publish regulations and executive orders. They make executive agreements which do not require ratification and sign treaties, which require approval by the ⅔ of the Senate. They also have the power to make a temporary appointment during the recess of the Senate and can grant "reprieves and pardons for offenses against the United States, except in cases of impeachment."

The Judiciary determines which laws Congress intended to apply in any given case, exercise judicial review and review the constitutionality of laws, determines how Congress meant the law to apply to disputes and determines how laws should be interpreted to assure uniform policies in a top-down fashion via the appeals process.

The system of Checks and Balance was designed and implemented by the founding fathers with such diligence that even after more than 225 years, it is still effective in preventing undue outreach by one of the three branches.

Note: Sites that have been referred to: 

1. https://www.law.cornell.edu/wex/separation_of_powers_0
2. https://avalon.law.yale.edu/18th_century/fed48.asp
3. https://www.britannica.com/topic/Congress-of-the-United-States
4. https://www.britannica.com/topic/House-of-Representatives-United-States-government
5. https://www.britannica.com/topic/Constitution-of-the-United-States-of-America
6. https://www.britannica.com/topic/executive-government
7. https://www.britannica.com/topic/checks-and-balances