키, 값 쌍 키 중복 X 순서 O Map Methods Method Description new Map() Creates a new Map set() Sets the value for a key in a Map get() Gets the value for a key in a Map delete() Removes a Map element specified by the key has() Returns true if a key exists in a Map forEach() Calls a function for each key/value pair in a Map entries() Returns an iterator with the [key, value] pairs in a Map size(Property) Re..