map._map.appendChild(div);
map is an object, call appendChild() in map; method div is a parameter
map is an instantiated object, _map is a div (that is, a map div), use the instantiated object to find _map
map is an object, call appendChild() in map; method div is a parameter
map is an instantiated object, _map is a div (that is, a map div), use the instantiated object to find _map