Fluid mechanics concerns itself with studying fluids: how they move, and how they react when forces act on them. A fluid is a substance that flows when force exerts upon it, and fluids include liquids, plasmas, and gases. The study of fluid mechanics dates back hundreds of years when Greeks began studying the dynamics of water. Later scientists expanded their studies to include other types of fluids. The applications of fluid mechanics are wide, from biology to mechanics to chemistry to astrophysics.
We can see fluids flow in many different ways in the world around us, and the study of fluid mechanics can open up other areas of study for you. Knowledge of fluid mechanics allows you to study weather patterns, the movement of gases in space, the movement of fluids in machines, and the human circulatory system. Fluid mechanics is a foundation of many other scientific disciplines.
Fluid mechanics is a broad discipline that touches many other areas of scientific study, so the list of careers that call on the knowledge of fluid dynamics is long, including physicists and engineers. Physicists in various specifications use their grasp of the concepts of fluid mechanics, and engineers in multiple disciplines rely on their studies. Fluid mechanics is crucial to the oil and gas industries, and it's important to biology, anatomy, and other disciplines of medicine. If you're looking for a career in just about any discipline of science, you're going to need a knowledge of fluid dynamics.
When you progress through online courses on Coursera about fluid dynamics, you can learn the basics of fluid dynamics as well as more specific topics like waves and vibrations, renewable energy, or aerodynamics as they relate to sports. Courses may help you understand thermodynamics, waves and vibrations, and the simulation and modeling of natural processes.