Pipe friction refers to the resistance that fluid experiences when flowing through a pipe. This resistance is caused by the interaction between the fluid and the pipe's inner surface, which can be affected by factors such as the pipe's material, diameter, and roughness. The greater the friction, the more energy is required to maintain the flow, which can impact the efficiency of systems like water supply and oil pipelines. Understanding pipe friction is essential for engineers and designers to ensure that fluid transport systems operate effectively. By calculating friction losses, they can determine the necessary pump power and select appropriate pipe sizes to minimize energy costs. This knowledge is crucial in various applications, including HVAC systems and industrial processes.