Google Maps Marker

I'm new in google maps, and I'm trying to learn it.

marker = new google.maps.Marker(
{
     map:map,
     draggable:true,
     animation: google.maps.Animation.DROP,
     position: results[0].geometry.location
});

This is my marker position, when I'm initialize the marker position than I know the place name (for example: XY street, New York,), but because of the draggable option it is changing, and my question is how can I get the new place name, what event handler do I need.