Historians define four types of imperial government: direct control, indirect control, rule by sphere of influence, and economic imperialism. "Modern World History" further categorizes imperial rule as being formal or informal, depending on whether the imperial nation officially establishes itself as the ruler of a colony.
Imperialist governments control the economy and political facilities of one or more colonies. The British empire's control of the American colonies prior to 1776 is an example of formal, direct imperial rule.
An empire administers direct control when its government offers no self-rule to the native population of the colony it controls. An empire makes use of indirect rule when it influences the ruling class of a native population to produce favorable conditions in the colony. Rule by sphere of influence occurs when a powerful country leverages its economic advantage to force a weaker country to provide it with exclusive trade rights.
Economic imperialism is a form of indirect rule in which private businesses native to the imperial government control large amounts of land in the colonial territory, often leading to significant influence in policy and legislation. The Dole Fruit Company's control of Hawaii before it was formally annexed as a U.S. state is an example of economic imperialism.