Parliamentarianism

A parliamentary system is a system of democratic governance of a state where the executive branch derives its democratic legitimacy from its ability to command the confidence of the legislature (parliament) and is also held accountable to that legislature. In a parliamentary system, the head of state is usually a different person 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 branch does not derive its democratic legitimacy from the legislature.

Countries with parliamentary systems may be constitutional monarchies, where a monarch is the head of state while the head of government is almost always a member of the legislature (such as the United Kingdom, Denmark, Sweden and Japan), 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, India and Italy). In a few parliamentary republics, such as Botswana, South Africa, and Suriname, as well as the German states, the head of government is also head of state, but is elected by and is answerable to the legislature.

Since ancient times, when societies were tribal, there were councils or a headman whose decisions were assessed by village elders. Eventually these councils have slowly evolved into the modern Parliamentary system.

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