The data types you meet most often are element collections (NodeList, HTMLCollection, Selecting Elements), attribute maps (NamedNodeMap of Attr, Processing Attributes), token lists (DOMTokenList from classList, Processing Classes), media TimeRanges (Timing Media Clips), Range and Selection (Range and Selection), DOMException (Handling Exceptions), DOMImplementation (Implementing a New Document) and DOMRect (Knowing the Bounding Rectangle).
None is a real Array. In Chrome 1 , NodeList and DOMTokenList have forEach(), HTMLCollection and NamedNodeMap only support for...of, and TimeRanges supports neither. Use Array.from(list) for map() or filter().