A smart key is a multi-function key that can unlock or start the engine with only one wireless device using the vehicle's two-way communication. The vehicle can recognize it and open the door or trunk without a separate locking device unlocking process just by carrying it and approaching it. In addition, it includes a welcome light function that illuminates the front of the driver's seat when approaching the vehicle at night, or an auto-lock function that locks the door after a set time if the door is out of a certain range without locking it. The digital key is a technology that implements the smart key function with a smartphone. You can use the feature by installing a dedicated application. When other people use the vehicle, it is possible to share the digital key with up to three people, and the sharing period ranges from a minimum of 6 hours to a maximum of 1 year.