Available on HTML5
HTMLCollection interface represents a generic collection (array-like object similar to arguments) of elements (in document order) and offers methods and properties for selecting from the list.
Returns the specific node at the given zero-based
index into the list. Returns
null if the
index is out of range.
Returns the specific node whose ID or, as a fallback, name matches the string specified by
name. Matching by name is only done as a last resort, only in HTML, and only if the referenced element supports the
name attribute. Returns
null if no node exists by the given name.