In this introductory chapter, we begin by revisiting key concepts from classical fluid mechanics for incompressible fluids, with a particular focus on fluid compartments in the human body, especially blood. We start by covering basic fluid dynamics principles, methods of study, and illustrative mathematical models for blood flow, expressed in terms of differential equations. The cardiovascular system is viewed as a fluid transport system, where both advection and diffusion transport mechanisms are present. Next, we review the clinical significance of arterial blood pressure, providing several examples. This is followed by a discussion of simple algebraic laws of flow, including Bernoulli’s, Darcy’s, and Poiseuille’s laws, as well as Starling’s principle of fluid exchange in the microvasculature. The elementary biofluid dynamics section continues with an exploration of blood rheology, viscosity, and their role in hemodynamics, with particular emphasis on the microvasculature. The final section addresses the regulation mechanisms of the cardiovascular system, within the context of bodily fluid dynamics, transport, and tissue perfusion. This chapter on fundamental fluid dynamics concepts serves as a bridge between Chap. 1 , which focuses on the human cardiovascular system, and the subsequent chapters on bodily fluids. The chapter concludes with a brief summary and suggestions for further reading.