Understanding the utility of project curves feature and revolved cut feature in solidworks

Objective: Understanding the utility of project curves feature and revolved cut feature in solidworks. FRONT FORK: https://drive.google.com/open?id=1nIhSoczTzlPF2DXL4hw-Bn-W6WciDOTL REAR WHEEL: https://drive.google.com/open?id=1VZ1l6XHMCsRFatCfupgyLWk_rsi2nJe5