In ancient times, power in societies might be understood to mean the determination of who lived from who died as exercised by a sovereign. Wars and executions were the tools of power.
Today, power is still the same but more subtle. States have replaced sovereigns in society and rather than war or executions, power is exercised through six major institutions.
Government, Big Pharma, Banks, the Media, Schools and the Military are the normalizing agents of power in modern society. If you think critically about it, life and death is still the business of power.