The book "Friction Phenomenon in Mechanical Design" provides a comprehensive overview of the role of friction in mechanical design. It begins with a historical examination of research on this topic, dating back to ancient Egypt. The authors, Dario Croccolo and Nicolò Vincenzi, highlight the early theories formulated by significant figures such as Leonardo da Vinci and acknowledge the outstanding contributions of Coulomb. The work goes beyond theoretical foundations and describes current mechanical applications where a precise understanding of friction coefficients is crucial for proper use and design. Additionally, valid methods for accurately measuring these coefficients are presented, which are applied in modern applications such as threaded connections and press fits, particularly in the front suspension of motorcycles.