Google maps setMap() and map options

Question

I am new to Google maps api v3. In the Google maps official tutorial, some of the sample code using

new google.maps.Marker({
 map: map    //Map option
});

or

new google.maps.Marker({
 //some options here
}).setMap(map);

What are the difference between each other?

Answer 1

Off the top of head:

1. You can create markers and add them to a map at a later time e.g. after clicking some button using setMap()
2. You can have multiple maps on one page. You can selectively add markers to any one of them using setMap()
3. You can also remove markers selectively from a map using setMap(null)