VTEC (Variable Valve Timing and Lift Electronic Control) is a system developed by Honda to improve the volumetric efficiency of a four-stroke internal combustion engine (i.e. improved economy). The VTEC system uses two camshaft profiles and hydraulically selects between profiles. It was invented by Honda engineer Ikuo Kajitani. It is distinctly different from standard VVT (variable valve timing) which advances the valve timing only and does not change the camshaft profile or valve lift in any way.