A fluid is described by the molecular structure it comprises of. The distance between these molecules depends upon the phase of fluid (gas, liquid or super critical). Molecules in a solid oscillate at an equilibrium point forming a lattice, where as when it is transformed into liquid the gain kinetic energy and start moving in an irregular pattern and further heating when the liquid vaporizes and turns into gaseous state the molecules start moving freely. The importance of fluid mechanics can be judged from the diversity of its presence. Atmospheric fluid can be seen by changing weather patterns in our environment and another example is the flow of blood in our body. Hence the criticality of fluid mechanics experimental investigation is reflected from its diverse applications.
Being a part of physics, fluid mechanics is deals in mechanics of fluids and studying the impact of forces on them. Fluid mechanics has evolved as the most diversely studied subject in recent times as its applications include mechanical engineering, biomedical engineering, chemical engineering, civil engineering, geophysics, astrophysics, and biology. Fluid mechanics lab is further divided into two sub categories namely fluid statistics which is the study of fluids at rest and fluid dynamics which is the study of fluids in motion. The importance of fluid mechanics these days is self explanatory as super computers are also needed for complex real time mathematical calculations in the subject. Hydrostatics is also a part of fluid mechanics and is fundamental of hydraulics the science of lifting and transporting materiel by storing energy.