What do colonialism and imperialism both require?

Colonialism: "the control or governing influence of a nation over a dependent country, territory, or people." Imperialism: "the policy of extending the rule or authority of an empire or nation over foreign countries, or of acquiring and holding colonies and dependencies." They are actually quite similar and each reinforces the other. The act of engaging in colonialism is an imperialistic act, but acts that are imperialistic are not always colonial. For example, (it's the only one I can think of, sorry if it's a bit contentious) some people define some of the America's current actions as imperialistic but they are not colonial. Hopefully that helps makes sense of things a little.Hope this helps!!