Learning from Leonardo

* While water, too, is compressible, the pressures required to obtain significant volume changes are so large that it can be assumed to be incompressible for all practical purposes.

† Strictly speaking, fluid mechanics is the study of fluids (gases and liquids), both static and in motion; fluid dynamics the study of fluids in motion; hydrodynamics the study of water in motion; while hydraulics (more of an engineering term) refers to the study of problems that have to do with water, both static and in motion.