Short answers, pulled from the story.
The word government derives from the Greek verb meaning to steer with a gubernaculum, or rudder, a metaphorical sense attested in the literature of classical antiquity including Plato's Ship of State. This ancient nautical metaphor reveals that the concept of governing was originally understood as the act of steering a community through turbulent waters, a role that has persisted for five thousand years since the first small city-states appeared.
History records the formations of early governments in Sumer, ancient Egypt, the Indus Valley civilization, and the Yellow River civilization by the third to second millenniums BC. One reason that explains the emergence of governments includes agriculture, as the Neolithic Revolution enabled people to specialize in non-agricultural activities, allowing some to rule over others as an external authority.
Plato in his book The Republic divided governments into five basic types, four being existing forms and one being Plato's ideal form which exists only in speech. Aristocracy is rule by law and order, timocracy is rule by honor and duty, oligarchy is rule by wealth, democracy is rule by pure liberty and equality, and tyranny is rule by fear.
The Soviet Union was the first large country to have a Communist government, marking a radical departure from previous systems, and since the fall of the Berlin Wall, liberal democracy has become an even more prevalent form of government. In the nineteenth and twentieth centuries, there was a significant increase in the size and scale of government at the national level, including the regulation of corporations and the development of the welfare state.
An independent, parallel distribution of powers between branches of government is the separation of powers, a model often called the trias politica model. However, in parliamentary and semi-presidential systems, branches of government often intersect, having shared membership and overlapping functions, creating a complex web of checks and balances.
More than half of the nations in the world are democracies, 97 of 167 as of 2021. However, the world is becoming more authoritarian with a quarter of the world's population under democratically backsliding governments, according to The Global State of Democracy 2021 by the International Institute for Democracy and Electoral Assistance.