In this world, most materials known to man are classified as solid, liquid, or gaseous. However, liquids and gases can also be classified into a common state which is the fluid state or fluids (Smits, 2000). Fluids are one of the most important elements in our lives. The water we drink, the air we breathe, the rivers that flow, the oil we use are all fluids. Fluids, as mentioned by Munson, Young, Okiishi, and Huebsch (2010), are defined as “a substance that continuously deforms when subjected to a shear stress of any magnitude” (p. 4). Fluids can also be described as a component that constantly undergoes physical changes due to shear force which is a force acting tangentially to its area (Massey & Ward-Smith, 2012). Fluids have some properties common to liquids and gases that differentiate them from solids, such as the ability to flow and change shape. However, fluid properties that are important in any engineering application are density, viscosity, surface tension, compressibility and bulk modulus, vapor pressure, and cavitation (refer to Figure 1 in the Appendix). In this information report, only the two main properties of fluids, namely density and viscosity, will be examined. Density and viscosity properties are further described. The first major property of fluids used in many types of applications is the density of the fluids. In engineering, density can be divided into three types which are mass or average density, specific gravity and also relative density or specific gravity. Mass or average density is the most commonly used type of density and is denoted by the Greek symbol r (rho) in units of kilogram per unit volume (kg/m3) (Munson, Young, Okii...... half of the article ......, and Jayaraman, G. (1996). Casson fluid flow in a tube filled with a homogeneous porous medium, International journal of engineering science, 34(6), 1145-1156.Douglas, J. F., Gasiorek. , J. M., Swaffield, J. A. and Jack, L. B. (2005). Fluid Mechanics (5th ed. London, England: Pearson Education Limited. Janna, W. S. (1993). MA: PWS Publishing Company. Massey, B. S. Ward-Smith, J. (2012) Fluid Mechanics (9th ed.: Spon Press.Munson, B.R., Young, D.F., Okiishi, T.H. and Huebsch, WW (2010). ): John Wiley & Sons, Inc. Smits, A. J. (2000). Sons, Inc. Streeter, V. L., Wylie, E. B. and Bedford, K. (1998) Fluid Mechanics (9th ed.: The McGraw-Hill Companies, Inc..)..