The three organs of government are legislative, judicial, and executive. Also known as the three branches, they provide a system of checks and balances to make sure that there is a separation of power so no single organ has too much power over the people. The legislative organ makes Federal laws. It is made up of the House of Representatives and the Senate. They also have the ability to declare war and regulate commerce along with controlling taxes and spending. The judicial branch is made up of the Supreme Court; its job is to interpret the Constitution and determine the supreme law of the land. Lastly, the executive branch is responsible for enforcing the laws. It is made up of the president and cabinet.

The three organs, or branches, of government are established under the model of the separation of powers. The Legislative, Judicial, and Executive branches all exercise power in different ways, offering checks and balances so no one organ has too much power.

The Legislative branch refers to the making of laws. In the United States, this consists of Congress, which is divided into the Senate and the House of Representatives. Each state has two senators and a varying amount of representatives based on population. Both are elected at the state level.

The Judicial branch is charged with the interpretation of the supreme law. In the US, this consists of the Supreme Court. They are meant for interpreting the law of the constitution in the context of changing times and circumstances.

The executive branch refers to the president and his cabinet. This usually refers to a complex and wide-ranging system of employees.

The three organs of government are the legislative, executive, and judicial. I will describe the role of each below. Most governments around the world, though arranged differently, exercise these powers in one way or another. Since many governments around the world have a system of government not unlike those of the United States and Great Britain, I have used them as illustrative examples:

• Legislative: This refers to making laws, a power usually vested in a representative assembly of some kind. In the federal government of the United States, Congress is the legislative branch. It is divided into two houses, each of which must approve potential legislation by a majority vote. In Great Britain, this power is held by Parliament.
• Executive: The executive power is broadly defined as the power to enforce, or carry out, laws. In the United States, this power belongs to the President and the Executive Branch. In most countries, the actual work of enforcing laws is done by an enormous and complex bureaucracy which the President is tasked with supervising. In Great Britain and other parliamentary systems, the executive power is exercised by a number of ministers who head offices similar to those in the United States.
• Judicial: The judicial branch basically interprets and applies laws, including the Constitution, through legal decisions. In the United States federal government, there is a judicial branch headed by a Supreme Court that mostly hears important constitutional cases on appeal. Beneath the Supreme Court there is a federal appeals court system and a district court system responsible for civil and criminal cases in federal law. In Great Britain, the judicial power is also held by a judiciary branch which has gradually become independent from Parliament (it was formally made independent in the 2000s.) 

Remember that in most governments, these powers can overlap. The President, for example, can issue executive orders that carry the power of law. Moreover, in the American system of government each branch is granted certain powers, or checks, over the others. The Presidential veto is one example of this power.