Government is the system of rules and responsibilities that a society establishes to accomplish collective goals and provide services that citizens need. Governments are found throughout the world and come in many forms. They may have different functions but most include providing law and order, setting the parameters of everyday life for citizens and often protecting them from outside interference or threats. Governments may also manage resources and provide for the general welfare of citizens such as education, military protection and infrastructure for transportation and communication.

The purpose of government is to protect and promote the well-being of its people through democratic means. This can be achieved by establishing systems that connect the citizens to the greater system in mutually beneficial ways that will ensure their safety and economic prosperity. Governments are the only entities capable of implementing these types of systems. They have the ability to tax, draw upon resources from an entire nation and compel citizen compliance. This is why most societies (at least those of a democratic nature) need a central authority to regulate, create laws and enforce them.

Most governments will have a judicial branch that oversees the activities of the other branches. The court structure and judicial appointments/elections are normally established by legislation or by the state constitution. Rulings made by state supreme courts are normally binding but they can be appealed to the United States Supreme Court.

Aside from the judicial branch, there are three levels of government; national, state and local. The national level is the top rung of the ladder and has the power to make federal laws. The senate and House of Representatives make up the legislative branch which makes up the second rung. The president and cabinet make up the executive branch and carry out laws made by Congress. The judicial branch evaluates these actions and can void laws that violate the Constitution or are unjust.

One of the important roles of a government is to manage externalities such as overfishing or global warming. This is a responsibility that cannot be handled by the market alone because private businesses will only be interested in maximizing profit and not considering all of the social consequences. In addition to managing externalities, governments can also create positive externalities such as building schools and hospitals or sending mail.

The framers of our Constitution created a system where each level of government has checks and balances to prevent abuse of power. This means that each level of government has to get the approval of the previous level before passing a law. It also means that citizens can influence the lawmaking process by attempting to persuade members of Congress or the president to change or veto laws they do not agree with. This separation of powers, known as checks and balances, slows the policymaking process but provides citizens with opportunities to influence the law as it progresses from initial idea to final implementation. This also gives them a sense of ownership over their laws since they can work to influence them at each stage.