The interaction between human operator and equipment in general can be made easier or harder depending on the effectiveness of the interface used for this interaction.The present work focuses on this interface - the so called ‘Human-Machine-Interface’ (HMI) for a specific set of equipments: the vehicles (passenger cars and commercial road vehicles).Vehicles need to be driven by professional and amateur drivers. The HMI of the vehicle needs, thus, to be adequate to a wide variety of drivers, allowing for a safe and enjoyable ride. The design of such an HMI must then consider several aspects that are human centered (physiological, psychological, sociological…) and machine centered (technological).The present work discusses briefly these aspects, their dynamics. The analysis of both vehicles and some other technology products are analyzed, and the trend of vehicle HMI's is drawn on a broad sense. It is shown that electronics play a key role in current HMI; and that this role is becoming more and more important.