What are the zones in a reservoir?

This video defines the zones found in a reservoir, specifically, the inactive, conservation, and flood zones. why are dams built, how do dams get built, what is hydropower, lake levels, Arkansas lake levels, Oklahoma lake levels, flood control projects, dam operations, how are dams operated, how are dams managed, dam management, how are reservoirs operated, how are reservoirs managed, reservoir management, lake management, lake operations, reservoir, dams, flood pool, flood control, water supply, spillway, surcharge, induced surcharge, reservoir zones, how do spillways work, what is the function of a spillway.