1 What it is  	 		What output shows you 
2 				when you write |console.log(typeof(variable);
3Undefined:					"undefined"
4Null:						"object"
5Boolean:					"boolean"
6Number:						"number"
7String:						"string"
8Function object:			"function"
9E4X XML object:				"xml"
10E4X XMLList object:			"xml"
11NodeList					"Nodelist [more data]"
12HTMLCollection				"HTMLCollection(1) [more data]"
13