What does submarine takes to move under water?

Submarines move underwater using a combination of buoyancy control, propulsion systems, and hydrodynamic design. They adjust their buoyancy by taking in or expelling water from ballast tanks, allowing them to sink or rise. Propulsion is typically provided by diesel-electric engines or nuclear reactors, which drive propellers. Additionally, the streamlined shape of the submarine helps reduce drag and allows for efficient movement through water.