Are you kidding? They supply water to fire hoses. You attach a fire hose and water comes out to put out a fire. Jeez... People these days.
The vertical hydraulic cylinder can be created for the drill.
Hydraulics can be used basically everywhere in day to day life. They are used in your heart, in car brakes, in water pistels and also in vehicles like diggers and cranes.
Hydraulics are used in air planes, cars, boats, constructional machines.
They are used by vehicals, engineering. They are used when vehicals move etc. They 'bounce'.