There are panels opening both sides at landing and cabin doors which opens to the left-right and center. This panels work automatically.
The passenger calls the lift where he is. When the lift arrives to the intended floor the doors open automatically. Automatic doors close when the passenger get inside the elevator. The user push the button where he would like to go. In a short time the lifts moves. The indicators shows the next passengers where the lift is going on through the lights on the cabin operating panel.
Thus many passenger benefit from the elevator. When there is no call to the lift, it automatically switch off itself until a new call.
Thanks to the photocell if there is anyone in front of the door it automatically open the doors. Thus the automatic door lifts are safer.