The Darcy friction factor is a dimensionless quantity used in fluid mechanics to quantify the resistance to flow in a pipe due to friction. It is essential for calculating pressure losses in fluid systems, particularly in turbulent flow conditions. The factor depends on the flow regime, pipe roughness, and Reynolds number, which characterizes the flow's behavior. In practical applications, engineers use the Darcy-Weisbach equation to determine the pressure drop in a pipe system. The Darcy friction factor can be obtained from empirical correlations or charts, such as the Moody chart, which provides a visual representation of the relationship between the friction factor, Reynolds number, and relative roughness.