Negatives: Imperialism led the world into the business of slave trading which then led to social discrimination around the world. Damaging the cultures and the built-up disunity among the natives ( the people who were colonized ). Imperialism also had stripped multiple countries off their natural resources and left nothing for those who were colonized.
Positives: With imperialism, the technology was improved by a ton. There were new crops to be found, new tools and easier farming methods for people. This all increased food production in the days which these changes meant a lesser amount of death to smaller colonies and nations. ( Overall improving the state of living to say ) Living longer lives and having a better sanitation compared to without or the early days of imperialism