Checks and Balances: Checks and balances refer to the system in which each branch of government has powers that limit or 'check' the powers of other branches in order to prevent abuse of power.
Separation of Powers: Separation of powers is the division of governmental responsibilities among different branches (executive, legislative, judicial) so no single branch has complete control over decisions.
Presidential Powers: Presidential powers are the authorities and responsibilities given to the President of the United States, as outlined in the Constitution.