Governments in terms of their key institutions

A parliamentary system or parliamentary democracy is a system of democratic governance of a state
where the executive derives its democratic legitimacy from its ability to gain the confidence of
the legislature, typically a parliament, and is also held accountable to that parliament. In a
parliamentary system, the head of state is usually a person distinct from the head of government.
This is in contrast to a presidential system, where the head of state often is also the head of
government and, most importantly, the executive does not derive its democratic legitimacy from the
legislature.

Countries with parliamentary democracies may be constitutional monarchies, where a monarch is the
head of state while the head of government is almost always a member of parliament (such as the
United Kingdom, Denmark, and Sweden), or parliamentary republics, where a mostly ceremonial
president is the head of state while the head of government is regularly from the legislature (such
as Ireland, Germany, and Italy). In bicameral parliaments, the head of government is generally,
though not always, a member of the lower house.

A presidential system is a democratic and republican government in which a head of government leads
an executive branch that is separate from the legislative branch. This head of government is in
most cases also the head of state, which is called “president”. In presidential countries, the
executive is elected and is not responsible to the legislature, which cannot in normal
circumstances dismiss it. Such dismissal is possible, however, in uncommon cases, often through
impeachment.

There is also a hybrid system called semi-presidentialism. It is a system of government in which a
president exists alongside a prime minister and a cabinet, with the latter being responsible to the
legislature of the state. It differs from a parliamentary republic in that it has a popularly
elected head of state, who is more than a mostly ceremonial figure, and from the presidential
system in that the cabinet, although named by the president, is responsible to the legislature,
which may force the cabinet to resign through a motion of no confidence. Such system can be found,
for example, in France or Russia.

The Czech Republic is a unitary parliamentary republic (despite the president being elected by the
people).

Parliament

is a legislative body of government. Generally, a modern parliament has three functions:
representing the electorate, making laws, and overseeing the government via hearings and inquiries
(the term is similar to the idea of a senate, synod or congress). Parliaments usually consist of
“chambers” or “houses”, and are usually either bicameral or unicameral.

In some parliamentary systems, the prime minister is a member of the parliament (e.g. in the United
Kingdom), whereas in others they are not (e.g. in the Netherlands). They are commonly the leader of
the majority party in the lower house of parliament, but only hold the office as long as the
"confidence of the house" is maintained. If members of the lower house lose faith in the leader for
whatever reason, they can call a vote of no confidence and force the prime minister to resign. The
parliamentary system can be contrasted with a presidential system, which operates under a stricter
separation of powers, whereby the executive does not form part of, nor is it appointed by, the
parliamentary or legislative body. In such a system, congresses do not select or dismiss heads of
governments, and governments cannot request an early dissolution as may be the case for
parliaments.

Separation of powers

is a system where a state's government is divided into branches, each with separate, independent
powers and responsibilities, so that powers of one branch are not in conflict with those of the
other branches. The typical division is into three branches: a legislature, an executive, and a
judiciary. (It can be contrasted with the fusion of powers in parliamentary and semi-presidential
systems, where the executive and legislative branches overlap.)

Separation of powers, therefore, refers to the division of responsibilities into distinct branches
of government by limiting any one branch from exercising the core functions of another. The intent
of separation of powers is to prevent the concentration of power by the system of checks and
balances.

The system of separations of powers is commonly ascribed to French Enlightenment political
philosopher Charles-Louis de Montesquieu, who described such system in his work The Spirit of the
Laws (1748).

Power

is the capacity of an individual to influence the conduct (behaviour) of others. The term
"authority" is often used for power that is perceived as legitimate by the social structure. The
use of power need not involve force or the threat of force (coercion). An example of using power
without oppression is the concept "soft power" (which comes from diplomacy, culture and history),
as compared to “hard power”.

Governments are perhaps the most familiar example of an authoritative social actor, because they
generally possess a monopoly on the legitimate use of physical force to compel obedience to their
mandates in a given geographic area. The soldier or police officer serves as an extension of state
authority and shares its legitimacy. However, even these familiar forms of political authority as
exercised by the state have limits set by the law.